Enclosures for treating materials

ABSTRACT

Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful intermediates and products, such as energy, fuels, foods or materials. For example, systems and methods are described that can be used to treat feedstock materials, such as cellulosic and/or lignocellulosic materials, in two or more vaults that can share a common wall.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT/US14/21604 filed Mar. 7, 2014which claims priority to the following provisional applications: U.S.Ser. No. 61/774,684, filed Mar. 8, 2013; U.S. Ser. No. 61/774,773, filedMar. 8, 2013; U.S. Ser. No. 61/774,731, filed Mar. 8, 2013; U.S. Ser.No. 61/774,735, filed Mar. 8, 2013; U.S. Ser. No. 61/774,740, filed Mar.8, 2013; U.S. Ser. No. 61/774,744, filed Mar. 8, 2013; U.S. Ser. No.61/774,746, filed Mar. 8, 2013; U.S. Ser. No. 61/774,750, filed Mar. 8,2013; U.S. Ser. No. 61/774,752, filed Mar. 8, 2013; U.S. Ser. No.61/774,754, filed Mar. 8, 2013; U.S. Ser. No. 61/774,775, filed Mar. 8,2013; U.S. Ser. No. 61/774,780, filed Mar. 8, 2013; U.S. Ser. No.61/774,761, filed Mar. 8, 2013; U.S. Ser. No. 61/774,723, filed Mar. 8,2013; and U.S. Ser. No. 61/793,336, filed Mar. 15, 2013. The fulldisclosure of each of these applications is incorporated by referenceherein.

BACKGROUND OF THE INVENTION

Many potential lignocellulosic feedstocks are available today, includingagricultural residues, woody biomass, municipal waste, oilseeds/cakesand seaweed, to name a few. At present, these materials are oftenunder-utilized, being used, for example, as animal feed, biocompostmaterials, burned in a co-generation facility or even landfilled.

Lignocellulosic biomass includes crystalline cellulose fibrils embeddedin a hemicellulose matrix, surrounded by lignin. This produces a compactmatrix that is difficult to access by enzymes and other chemical,biochemical and/or biological processes. Cellulosic biomass materials(e.g., biomass material from which the lignin has been removed) is moreaccessible to enzymes and other conversion processes, but even so,naturally-occurring cellulosic materials often have low yields (relativeto theoretical yields) when contacted with hydrolyzing enzymes.Lignocellulosic biomass is even more recalcitrant to enzyme attack.Furthermore, each type of lignocellulosic biomass has its own specificcomposition of cellulose, hemicellulose and lignin.

SUMMARY

Generally, the inventions relate to enclosures for treating materials,such as biomass. The inventions also relate to facilities, methods andsystems for producing products from a biomass material. Increasingthroughput, safety and costs associated with treatment of biomass arekey goals in the development of useful manufacturing processes. Inmethods involving irradiation, the throughput can be increased bymultiple irradiations with more than one irradiation device. Hazards canbe mitigated and safety enhanced by enclosing the irradiation devices inradiation opaque enclosures, for example a vault. To reduce the energyand material costs associated with the building materials used toconstruct the vault and transportation or conveying of the biomassbetween vaults during processing, sharing of walls between vaults hasbeen found effective. The methods and systems disclosed herein includetwo or more treatment vaults (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,14, 15, 16, 17, 18, 19, 20, or more e.g., 22, 24, 28, or more, sharingone or more common walls. Generally, the methods include treating arecalcitrant biomass with electron beams and then biochemically andchemically processing the reduced recalcitrance material to, forexample, ethanol, xylitol and other products.

In one aspect, the invention includes processing (e.g., treating)materials, such as biomass materials, in at least a first and a secondenclosure (e.g., vault, vaults or a system of vaults). The walls of theenclosures can be fabricated from discrete interconnecting blocks toprovide photon-tight structures. Optionally, the first and secondenclosures share one or more common walls. The method can includeconveying the biomass material through the first enclosure and exposingthe biomass material to a first dose of ionizing radiation (e.g.,exposing in the first enclosure) to produce a first treated biomassmaterial. Optionally, the method can include conveying the biomassmaterial into the first enclosure and then conveying the first treatedbiomass material out of the first enclosure and into the secondenclosure. Optionally, the second treated biomass material can beconveyed out of the second enclosure. Optionally, the first dose ofradiation can be between about 0.5 Mrad and about 20 Mrad, such asbetween about 1 Mrad and about 15 Mrad, or between about 5 Mrad andabout 15 Mrad. The method can include conveying the first treatedbiomass material through the second enclosure and exposing the firsttreated biomass material to a second dose of ionizing radiation (e.g.,exposing in the second enclosure) to produce a second treated biomassmaterial. Optionally, the sum of the first and second doses that areapplied in the first and second enclosures can be between about 10 Mradand about 40 Mrad, such as between about 20 Mrad and about 40 Mrad, suchas between about 15 Mrad and about 35 Mrad or between about 15 Mrad andabout 30 Mrad. The first and second doses of ionizing radiation can beapplied using accelerated electrons from one or more electronaccelerators, for example, the accelerated electrons having an energy ofbetween about 0.3 MeV and about 5 MeV (e.g., such as between about 0.5MeV and about 3.5 MeV or between about 0.8 MeV and about 2 MeV). Thefirst and second doses of ionizing radiation can be applied usingaccelerated electrons (e.g., using an electron accelerator), whereineach accelerator can be operating at a power of between about 100 kW andabout 400 kW, such as between about 100 kW and about 300 kW, such asbetween about 100 kW and about 250 kW or between about 100 kW and about200 kW. Optionally, the biomass material and/or the first treatedbiomass material is/are moved by a vibratory conveyor through and/orwithin the enclosure(s). Optionally, conveying through each enclosureoccurs continuously, for example a vibratory conveyor can be used forcontinuously conveying the material within an enclosure. Optionally,processing of the material occurs at a rate of between about 1,000 lbper hour and about 10,000 lb per hour, such as between about 2,000 lbper hour and about 6,000 lb per hour or between about 2,000 lb per hourand about 5,000 lbs per hour. Optionally, the processing can even begreater than about 10,000 lb per hour, such as greater than about 15,000lb per hour, greater than about 20,000 lb per hour, greater than about25,000 lb per hour. For example, the material can be conveyed throughthe enclosures (e.g., while being treated) at a rate of between about1,000 lb per hour and about 10,000 lb per hour, between about 2,000 lbper hour and about 6,000 lb per hour, between about 2,000 lb per hourand about 5,000 lb per hour. Optionally, the biomass can be conveyedthrough the enclosures (e.g., while being treated) at a rate greaterthan about 10,000 lb per hour, greater than about 15,000 lb per hour,greater than about 20,000 lb per hour, or even greater than about 25,000lb per hour.

In some aspects of the invention including treating biomass material inat least a first and a second enclosure, the biomass material can betransported or conveyed to the first enclosure and optionallytransported or conveyed to the second enclosure for a second treatment.The biomass material can even be optionally transported or conveyed tomore enclosures (e.g., a third, a fourth, a fifth, a sixth enclosure)for additional treatments (e.g., a third treatment, a fourth treatment,a fifth treatment, a sixth treatment; to produce a third, fourth, fifthor sixth treated biomass respectively). Transporting or conveying caninclude, for example, utilizing a pneumatic conveyor system and/or ascrew conveyer system, such as a cooled screw conveyer system.Optionally, transporting or conveying to and from (e.g., into or out ofthe enclosures), and between the conveyors occurs continuously. In someaspects, heat generated during treating biomass in an enclosure (e.g., avault) can be transferred to another process. For example, the hotbiomass can be transferred directly to a saccharification step, whereinthe heat aids in hearing liquids and enzymes used in this step.Optionally or additionally, the heat is transferred utilizing a heatexchanger.

In another aspect the invention relates to a biomass treatment facilityincluding at least a first and a second enclosure. The facility includesa first conveying system configured to convey the biomass materialthrough the first enclosure while exposing the biomass material to afirst dose of ionizing radiation from a first electron accelerator toproduce a first treated biomass material. The facility can include asecond conveying system configured to convey the first treated biomassmaterial through the second enclosure while exposing the first treatedbiomass material to a second dose of ionizing radiation from a secondelectron accelerator to produce a second treated biomass material.Optionally, the first and the second accelerator operate at a power ofbetween about 100 and 400 kW, such as between about 100 kW and about 300kW, such as between about 100 kW and 250 kW or between about 100 kW andabout 200 kW. The facility enclosures (e.g., the first enclosure and thesecond enclosure) can be fabricated from discrete interconnecting blocksconfigured to provide a photo-tight structure. Optionally, theenclosures (e.g., the first and the second enclosure) can share a commonwall.

Implementations of the invention can optionally include one or more ofthe following summarized features. In some implementations, the selectedfeatures can be applied or utilized in any order while in otherimplementations a specific selected sequence is applied or utilized.Individual features can be applied or utilized more than once in anysequence and even continuously. In addition, an entire sequence, or aportion of a sequence, of applied or utilized features can be applied orutilized once, repeatedly or continuously in any order. In some optionalimplementations, the features can be applied or utilized with different,or where applicable the same, set or varied, quantitative or qualitativeparameters as determined by a person skilled in the art. For example,parameters of the features such as size, individual dimensions (e.g.,length, width, height), location of, degree (e.g., to what extent suchas the degree of recalcitrance), duration, frequency of use, density,concentration, intensity and speed can be varied or set, whereapplicable, as determined by a person of skill in the art.

Features, for example, include: A method of processing materials, suchas a biomass material, including conveying a biomass material through afirst enclosure and exposing the biomass material to a first dose ofionizing radiation to produce a first treated biomass material;conveying an ionizing radiation treated biomass material through anenclosure and exposing ionizing radiation treated biomass material to adose of ionizing radiation to produce and additionally treated biomassmaterial; utilizing an enclosures that can share one or more commonwalls; utilizing doses of ionizing radiation that can be applied usingaccelerated electrons from one or more electron accelerators; utilizingelectrons that are accelerated to an energy between about 0.3 MeV andabout 5 MeV; utilizing electrons that are accelerated to an energybetween about 0.5 MeV and about 3.5 MeV; utilizing electrons that areaccelerated to an energy between about 0.8 MeV and about 2 MeV; applyinga first radiation dose to a biomass material of between about 0.5 Mradand about 20 Mrad; applying a first radiation dose to a biomass materialof between about 1 Mrad and about 15 Mrad; applying a first radiationdose to a biomass material of between about 5 Mrad and about 15 Mrad;applying a sum of a first and a second dose to a biomass material ofbetween about 10 Mrad and about 40 Mrad; applying a sum of a first and asecond dose to a biomass material of between about 20 Mrad and about 40Mrad; applying a sum of a first and a second dose to a biomass materialof between about 15 Mrad and about 35 Mrad; applying a sum of a firstand a second dose to a biomass material of between about 15 Mrad andabout 30 Mrad; utilizing enclosures that are fabricated from discreteinterconnecting blocks; utilizing enclosures with walls that providephoton-tight structures; conveying a biomass material into a firstenclosure and treating it, and then conveying the first treated biomassout of the first enclosure and into the second enclosure; conveying abiomass material into a first enclosure and treating it, and thenconveying the first treated biomass out of the first enclosure and intothe second enclosure, and conveying a second treated biomass materialout of the second enclosure; conveying a biomass material that has beentreated in two enclosures into a third enclosure, conveying the biomasswithin the third enclosure and exposing the treated biomass material toanother dose of ionizing radiation to produce a third treated biomassmaterial; utilizing a pneumatic conveyor system and/or a screw conveyersystem; conveying into and/or out of enclosures continuously; a biomassmaterial and treated biomass material is conveyed by a vibratoryconveyor within an enclosures; a biomass material or treated biomassmaterial are conveyed by a vibratory conveyor within an enclosures;conveying with a vibratory conveyor continuously; processing of amaterial at an average rate of from about 1,000 lb per hour to about10,000 lb per hour; processing of a material at an average rate of fromabout 2,000 lb per hour to about 6,000 lb per hour; processing of amaterial at an average rate of from about 2,000 lb per hour to about5,000 lb per hour; processing of a material at an average rate of atleast about 15,000 lb per hour; processing of a material at an averagerate of at least about 20,000 lb per hour; processing of a material atan average rate of at least about 25,000 lb per hour; conveying of amaterial at a rate of from about 1,000 lb per hour to about 10,000 lbper hour; conveying of a material at a rate of from about 2,000 lb perhour to about 6,000 lb per hour; conveying of a material at rate of fromabout 2,000 lb per hour to about 5,000 lb per hour; conveying of amaterial at a rate of from about 1,000 lb per hour to about 10,000 lbper hour; conveying of a material at a rate of at least about 15,000 lbper hour; conveying of a material at a rate of at least about 20,000 lbper hour; conveying of a material at a rate of at least about 25,000 lbper hour; applying a first and second dose of ionizing radiation to amaterial using accelerated electrons produced by an accelerator, eachaccelerator operating at a power of between about 100 kW to about 400kW; applying a first and second dose of ionizing radiation to a materialusing accelerated electrons produced by an accelerator, each acceleratoroperating at a power of between about 100 kW to about 300 kW; applying afirst and second dose of ionizing radiation to the material usingaccelerated electrons produced by an accelerator, each acceleratoroperating at a power between about 100 kW and about 250 kW; applying afirst and second dose of ionizing radiation to the material usingaccelerated electrons produced by an accelerator, each acceleratoroperating at a power between about 100 kW and about 200 kW; a biomasstreatment facility including a first conveying system configured toconvey a biomass material through a first enclosure while exposing thebiomass material to a first dose of ionizing radiation from a firstelectron accelerator to produce a first treated biomass material; asecond conveying system configured to convey a first treated biomassmaterial through a second enclosure while exposing the first treatedbiomass material to a second dose of ionizing radiation from a secondelectron accelerator to produce a second treated biomass material; afirst and second enclosure that share a common wall; utilizing one ormore accelerators that operate at a power of between about 100 kW andabout 300 kW; utilizing one or more accelerator that operate at a powerof between about 100 kW and 250 kW; utilizing one or more accelerator ata power of between about 100 kW and about 200 kW; utilizing a first andsecond enclosure with walls that are fabricated from discreteinterconnecting blocks configured to provide a photo-tight structure.

Other features and advantages of the invention will be apparent from thefollowing detailed description, and from the claims.

DESCRIPTION OF THE DRAWING

The foregoing will be apparent from the following more particulardescription of example embodiments of the invention, as illustrated inthe accompanying. The drawings are not necessarily to scale, emphasisinstead being placed upon illustrating embodiments of the presentinvention.

FIG. 1 is a flow diagram showing processes for manufacturing sugarsolutions and products derived therefrom.

FIG. 2 is a flow diagram showing a process for treating a biomassmaterial in two vaults sharing a common wall.

FIG. 3A is a perspective view showing two vaults for treating biomasswhere the vaults share a common wall. FIG. 3B is a front side view. FIG.3C is a top side view.

FIG. 4 is a perspective view showing two vaults for treating biomass anda flow path for material processing.

DETAILED DESCRIPTION

Using the methods and systems described herein, cellulosic andlignocellulosic feedstock materials, for example that can be sourcedfrom biomass (e.g., plant biomass, animal biomass, paper, and municipalwaste biomass) and that are often readily available but difficult toprocess, can be turned into useful products (e.g., sugars such as xyloseand glucose, and alcohols such as ethanol and butanol). Included aremethods and systems for treating biomass in two or more vaults sharingtwo or more common walls. These same methods and systems can also beutilized to treat starchy materials and hydrocarbon containingmaterials.

Referring to FIG. 1, processes for manufacturing sugar solutions andproducts derived therefrom include, for example, optionally mechanicallytreating a cellulosic and/or lignocellulosic feedstock 110. Beforeand/or after this treatment, the feedstock can be treated with anotherphysical treatment, for example irradiation, to reduce, or furtherreduce its recalcitrance 112. A sugar solution is formed bysaccharifying the feedstock 114 by, for example, the addition of one ormore enzymes 111. A product can be derived from the sugar solution, forexample, by fermentation to an alcohol 116. Further processing 124 caninclude purifying the solution, for example by distillation. If desired,the steps of measuring lignin content 118 and setting or adjustingprocess parameters based on this measurement 120 can be performed atvarious stages of the process, for example, as described in U.S. Pat.No. 8,415,122 issued Apr. 9, 2013, the complete disclosure of which isincorporated herein by reference.

The treatment step 112 can be irradiation with an electron beam. Severalprocesses can occur in biomass when electrons from an electron beaminteract with matter in inelastic collisions. For example, ionization ofthe material, chain scission of polymers in the material, cross linkingof polymers in the material, oxidation of the material, generation ofX-rays (“Bremsstrahlung”) and vibrational excitation of molecules (e.g.,phonon generation). Without being bound to a particular mechanism, thereduction in recalcitrance can be due to several of these inelasticcollision effects, for example ionization, chain scission of polymers,oxidation and phonon generation. Some of the effects (e.g., especiallyX-ray generation), necessitate shielding and engineering barriers, forexample, enclosing the irradiation processes in a concrete (or otherradiation opaque material) vault. Another effect of irradiation,vibrational excitation, is equivalent to heating up the sample. Heatingthe sample by irradiation can help in recalcitrance reduction, butexcessive heating can destroy the material, as will be explained below.

The adiabatic temperature rise (ΔT) from adsorption of ionizingradiation is given by the equation: ΔT=D/Cp: where D is the average dosein kGy, Cp is the heat capacity in J/g ° C., and ΔT is the change intemperature in degrees Celsius. A typical dry biomass material will havea heat capacity close to 2. Wet biomass will have a higher heat capacitydependent on the amount of water since the heat capacity of water isvery high (4.19 J/g ° C.). Metals have much lower heat capacities, forexample 304 stainless steel has a heat capacity of 0.5 J/g ° C. Theestimated temperature change due to the instant adsorption of radiationin a biomass and stainless steel for various doses of radiation is shownin Table 1. At the higher temperatures biomass will decompose causingextreme deviation from the estimated changes in temperature.

TABLE 1 Calculated Temperature increase for biomass and stainless steel.Dose (Mrad) Estimated Biomass ΔT (° C.) Steel ΔT (° C.) 10 50 200 50 250(Decomposition) 1000 100 500 (Decomposition) 2000 150 750(Decomposition) 3000 200 1000 (Decomposition)  4000

High temperatures can destroy and or modify the biopolymers in biomassso that the polymers (e.g., cellulose) are unsuitable for furtherprocessing. A biomass subjected to high temperatures can become dark,sticky and give off odors indicating decomposition. The stickiness caneven make the material hard to convey. The odors can be unpleasant andbe a safety issue. In fact, keeping the biomass below about 200° C. hasbeen found to be beneficial in the processes described herein (e.g.,below about 190° C., below about 180° C., below about 170° C., belowabout 160° C., below about 150° C., below about 140° C., below about130° C., below about 120° C., below about 110° C., between about 60° C.and 180° C., between about 60° C. and 160° C., between about 60° C. and150° C., between about 60° C. and 140° C., between about 60° C. and 130°C., between about 60° C. and 120° C., between about 80° C. and 180° C.,between about 100° C. and 180° C., between about 120° C. and 180° C.,between about 140° C. and 180° C., between about 160° C. and 180° C.,between about 100° C. and 140° C., between about 80° C. and 120° C.).

It has been found that irradiation above about 10 Mrad is desirable forthe processes described herein (e.g., reduction of recalcitrance). Ahigh throughput is also desirable so that the irradiation does notbecome a bottle neck in processing the biomass. The treatment isgoverned by a Dose rate equation: M=FP/D·time, where M is the mass ofirradiated material (kg), F is the fraction of power that is adsorbed(unit less), P is the emitted power (kW=Voltage in MeV×Current in mA),time is the treatment time (sec) and D is the adsorbed dose (kGy). In anexemplary process where the fraction of adsorbed power is fixed, thePower emitted is constant and a set dosage is desired, the throughput(e.g., M, the biomass processed) can be increased by increasing theirradiation time. However, increasing the irradiation time withoutallowing the material to cool, can excessively heat the material asexemplified by the calculations shown above. Since biomass has a lowthermal conductivity (less than about 0.1 Wm-1K−1), heat dissipation isslow, unlike, for example, metals (greater than about 10 Wm-1K−1) whichcan dissipate energy quickly as long as there is a heat sink to transferthe energy to.

A solution to the aforementioned contrasting issues, the need for a highradiation dose and rapid processing, without excessively heating theirradiated material, is to irradiate the biomass with one irradiator,allow the biomass to cool, and then irradiate the material with a secondirradiator in a continuous manner. Higher throughput can be obtained byusing even more irradiators (e.g., 3, 4, 5 or even more) but the costsof equipment and energy also increase.

The systems and methods disclosed herein provide a possible solution forthe safe and efficient processing of biomass. In particular, in order toincrease the throughput of processing feedstock with irradiation, theprocessing can include applying to the feedstock more than one dose ofradiation (e.g., more than one pass through a radiation beam). FIG. 2shows a method to increase the throughput of processing feedstock withirradiation, for example, to reduce its recalcitrance, and utilizing twovaults. The two vaults can have a common wall. The process includesconveying the biomass into a first treatment vault 210. Within the firsttreatment vault, the biomass is irradiated while being conveyed by aconveyor 220. After the first irradiation, the biomass is conveyed outof the first treatment vault and into a second treatment vault 230. Thebiomass is irradiated in the second treatment vault 240. After thesecond treatment, the biomass is conveyed out of the second vault 250,and can be further processed and/or collected. The steps of conveyingand irradiating can be repeated with a third, fourth or more vaults andconveyors. In another embodiment the material to be irradiated isconveyed to a single vault, irradiated, conveyed out of the vault,conveyed back into the same vault and then irradiated for a second timein the same vault. Permutation and combinations of these embodiments arealso possible, for example irradiating twice in the first vault with orwithout conveying the material out of the vault, then conveying toanother vault and irradiating the material. During the treatments in thevault, heat can be generated, for example, due to irradiation of abiomass and equipment as discussed. The heat can be removed from thebiomass by a heat exchanger, for example a screw cooler or cooledconveyor. Optionally the heat can be utilized/transferred to otherprocesses. For example, the heat 260 can be utilized for furtherprocessing of the material. For example, saccharification of anirradiated biomass material. In some instances, a biomass material canbe irradiated and transferred without cooling directly into an aqueoussolution, wherein the heated biomass aids in heating the water, forexample by at least about 1° C. (e.g., at least about 2° C., at least 5°C., at least about 10° C., at least about 20° C.).

For processes wherein the biomass is treated twice, the biomass needs tobe conveyed or transported from one vault to the other betweentreatments. The energy utilized conveying the material between the firstand second vault increases with the distance between the vaults. Inaddition, the material (e.g., building and/or equipment) costs arehigher with increasing distance between the vaults. The least costs withrespect to conveying the material would be in a configuration whereinsequential irradiation vaults are placed side by side with walls incontact.

In some embodiments, the biomass is allowed to cool between treatments,e.g., irradiations. This can be accomplished by the design of the twovaults. Therefore, in some embodiments, the distance between the vaultsis sized to allow the biomass to cool at least about 5° C. e.g., atleast about 10° C., at least about 15° C., at least about 20° C., atleast about 30° C., at least about 40° C., at least about 50° C. Coolingcan be by heat exchange with the ambient environment and/or by a heatexchange system (e.g., cooling screw, cooled conveyor). The distancebetween the vaults can be determined by the cooling rate of the biomassand the conveying rate between irradiations.

An alternative to having two discrete vaults side by side is shown in aperspective view in FIG. 3A. In this embodiment the two vaults share acommon wall 310. This configuration allows the vaults to be in theclosest proximity while still forming two irradiation vaults. Thedistance to convey the biomass material between vault 1 302 and vault 2304 has also been minimized, providing cost advantages with respect toconveying the materials. In addition, by sharing a wall, material forconstruction of the walls has been reduced. Other embodiments includehaving three, four or more vaults sharing common walls. As more wallsare shared between vaults, it is clear that the savings in material(e.g., building and/or equipment) would increase since arrangements withvaults sharing 2, 3 or even 4 walls can be envisioned.

Components and systems that can be used with the vaults will be outlinedwith reference to; the perspective view FIG. 3A, a front side view FIG.3B, and a top side view FIG. 3C. An inlet 320 for a first enclosedconveyor 325 is situated at the end of pipe 327 where it is joined toconveyor 325. Material (e.g., biomass) is fed pneumatically by a pipe327 through the inlet to the conveyor. The first conveyor is orientedperpendicularly and above the second conveyor 330 as shown. Material canbe conveyed from the inlet of the first conveyor, traverse the length ofthe first conveyor and be then dumped onto the second conveyor. Thefirst conveyor can have a cross cut conveying surface distal to theinlet 320. This cross can help to evenly distribute (e.g., dump, pore)the conveyed material onto the second conveyor 330. The second conveyorconveys the biomass material under the scan horn 340 and then dumps thematerial into the hopper (hopper 350 shown only in FIG. 3B through arotary valve 360. The biomass is pneumatically conveyed out of thehopper through a tube 365 and passes through the ceiling of the vaultwhere it can be sent to the inlet of the second vault.

Also shown in the FIGS. 3A, 3B and/or 3C are an electron beamaccelerator 370 with a tube (vacuum tube) for accelerating electrons.The electron beam accelerator is mounted on and extends through theceiling. A power source 380 for the electron beam accelerator is alsomounted on the ceiling. An electrical conduit 382 from the power sourceto the electron beam accelerator is also shown. The conveyors andassociated equipment are mounted on rails, 390 and 391, so that theconveyors can be moved out from under the irradiation equipment (e.g.,the scan horn and electron beam accelerator). A vent system 395 fordrawing out air from the vault is also shown. Similar systems andequipment can be used in the second vault 304. The vaults are built on aconcrete slab 397 and the ceilings and walls are made of structurallyresilient and radiation opaque materials (e.g., concrete, lead,stainless steel, rebar). Enclosures (not shown) can be provided withinthe vault to protect components of the conveying equipment or otherequipment.

FIG. 4 is another perspective view showing a possible path of a materialthat is irradiated twice, once in vault 1, 302 and then in vault 2, 304.In addition to being conveyed from vault 1 to vault 2, the material canbe further processed between the vaults. For example, at 410 the biomasscan be cooled, comminuted, sampled, diverted and/or screened. Forexample, the materials can be conveyed, using cooled screw conveyors,cooled vibratory conveyors, pneumatic systems such as closed loop gasconveying systems.

Another possible configuration to allow multiple treatments and minimizeconveying costs between irradiators is to have more than one electronbeam device enclosed in a single vault. However, in such aconfiguration, if equipment in one of the vaults needs to be accessedthen all the irradiators in that vault need to be taken off line forsafety reasons. This can create a significant reduction in throughputand operator attention with concomitant financial losses. In embodimentswith two or more vaults sharing two or more common walls, access toequipment associated with one irradiation device does not require otherirradiation devices in other vaults to be taken off line. In thesecases, the vault that is not being used can be by-passed, for example,by diverting the flow of biomass to other vaults with operatingirradiators.

The flow of biomass into and between vaults can be re-directed asneeded. For example, a first vault that was used for a first treatmentof un-irradiated biomass can be bypassed and the biomass can be sent toa second vault that was being used for treating biomass for a seconddose of radiation. The once treated biomass treated by this second vaultcan then be sent to a third vault where the biomass can be treated for asecond time. The flow of biomass can also be diverted so that thebiomass is sent to the same vault for treatment twice. This control offlow can be done by physically moving the necessary pneumatic systemssuch as pumps, blowers, dust bags and tubing. Alternatively, thepneumatic system can include a system of components interconnectedbetween the vaults and the flow controlled by opening and closing valvesand/or turning on or off pumps and/or turning on or off blowers.

The radiation dose applied in the first vault can be approximately thesame as the radiation dose applied in the second vault. Alternatively,the radiation dose in two vaults can be different in each vault. Forexample, the radiation dose in a first vault can be less than about 50%of the total dose utilized in the irradiation (e.g., less than about40%, less than about 30%, less than about 20%, less than about 10%). Ifmore than two vaults are used in the irradiation, the radiation doseapplied can be approximately the same in each vault or the radiationdose can be different in each vault.

The biomass can be treated continuously with the methods disclosedherein. In some embodiments the average rate of processing a biomass ismore than about 500 lb/hr (e.g., more than about 1000 lb/hr, more thanabout 1500 lb/hr, more than about 2000 lb/hr, more than about 2500lb/hr, more than about 3000 lb/hr, more than about 3500 lb/hr, more thanabout 4000 lb/hr, more than about 4500 lb/hr, more than more than about5000 lb/hr, more than about 6000 lb/hr, more than about 10,000 lb/hr,more than about 15,000 lb/hr, more than about 20,000 lb/hr, more thanabout 25,000 lb/hr, for example; between about 1000 and 25,000 lb/hr,between about 1000 and 20,000 lb/hr, between about 1000 and 10,000lb/hr, between about 1000 and 5000 lb/hr, between about 5000 and 25,000lb/hr). The material can be processed at lower rates as well, e.g.,below 500 lb/hr or below 100 lb/hr. The rates of conveying the materialunder an electron beam can vary greatly and independently between theirradiators in various vaults. For example, the conveying rate can beslowed down to increase the irradiation dose or increased to decreasethe irradiation dose.

The vaults are designed to contain radiation as well as house theirradiation devices and associated equipment. Preferably the vaults arebuilt with radiation opaque materials, for example concrete, lead,steel, soil or combinations of these. An example of a vault material isconcrete which has a halving-thickness (the thickness to reduce theradiation by half) of 2.4″. Therefore, walls can be about 4 feet thickwhich would reduce radiation striking the walls to one millionth of theoriginal strength. For a dose of 250 kGy applied inside the structure,the resulting radiation outside the structure, assuming an F-factor of1.0, will be 0.25 microrem, well below safe limits. Walls can be thinneror thicker, for example, between 3 and 12 feet thick. In addition towalls, floors and ceilings, the vaults can have doors made of radiationopaque materials. The materials can be layered, for example, doors canbe made as layers of 1″ lead over 6″ of steel over 1″ of lead.

Some more details and reiterations of processes for treating a feedstockthat can be utilized, for example, with the embodiments alreadydiscussed above, or in other embodiments, are described in the followingdisclosures.

Radiation Treatment

The feedstock can be treated with radiation to modify its structure toreduce its recalcitrance. Such treatment can, for example, reduce theaverage molecular weight of the feedstock, change the crystallinestructure of the feedstock, and/or increase the surface area and/orporosity of the feedstock . . . Radiation can be by, for exampleelectron beam, ion beam, 100 nm to 28 nm ultraviolet (UV) light, gammaor X-ray radiation. Radiation treatments and systems for treatments arediscussed in U.S. Pat. No. 8,142,620 and U.S. patent application Ser.No. 12/417,731, the entire disclosures of which are incorporated hereinby reference.

Each form of radiation ionizes the biomass via particular interactions,as determined by the energy of the radiation. Heavy charged particlesprimarily ionize matter via Coulomb scattering; furthermore, theseinteractions produce energetic electrons that may further ionize matter.Alpha particles are identical to the nucleus of a helium atom and areproduced by the alpha decay of various radioactive nuclei, such asisotopes of bismuth, polonium, astatine, radon, francium, radium,several actinides, such as actinium, thorium, uranium, neptunium,curium, californium, americium, and plutonium. Electrons interact viaCoulomb scattering and bremsstrahlung radiation produced by changes inthe velocity of electrons.

When particles are utilized, they can be neutral (uncharged), positivelycharged or negatively charged. When charged, the charged particles canbear a single positive or negative charge, or multiple charges, e.g.,one, two, three or even four or more charges. In instances in whichchain scission is desired to change the molecular structure of thecarbohydrate containing material, positively charged particles may bedesirable, in part, due to their acidic nature. When particles areutilized, the particles can have the mass of a resting electron, orgreater, e.g., 500, 1000, 1500, or 2000 or more times the mass of aresting electron. For example, the particles can have a mass of fromabout 1 atomic unit to about 150 atomic units, e.g., from about 1 atomicunit to about 50 atomic units, or from about 1 to about 25, e.g., 1, 2,3, 4, 5, 10, 12 or 15 atomic units.

Gamma radiation has the advantage of a significant penetration depthinto a variety of material in the sample.

In embodiments in which the irradiating is performed withelectromagnetic radiation, the electromagnetic radiation can have, e.g.,energy per photon (in electron volts) of greater than 102 eV, e.g.,greater than 103, 104, 105, 106, or even greater than 107 eV. In someembodiments, the electromagnetic radiation has energy per photon ofbetween 104 and 107, e.g., between 105 and 106 eV. The electromagneticradiation can have a frequency of, e.g., greater than 1016 Hz, greaterthan 1017 Hz, 1018, 1019, 1020, or even greater than 1021 Hz. In someembodiments, the electromagnetic radiation has a frequency of between1018 and 1022 Hz, e.g., between 1019 to 1021 Hz.

Electron bombardment may be performed using an electron beam device thathas a nominal energy of less than 10 MeV, e.g., less than 7 MeV, lessthan 5 MeV, or less than 2 MeV, e.g., from about 0.5 to 1.5 MeV, fromabout 0.8 to 1.8 MeV, or from about 0.7 to 1 MeV. In someimplementations the nominal energy is about 500 to 800 keV.

The electron beam may have a relatively high total beam power (thecombined beam power of all accelerating heads, or, if multipleaccelerators are used, of all accelerators and all heads), e.g., atleast 25 kW, e.g., at least 30, 40, 50, 60, 65, 70, 80, 100, 125, or 150kW. In some cases, the power is even as high as 500 kW, 750 kW, or even1000 kW or more. In some cases the electron beam has a beam power of1200 kW or more, e.g., 1400, 1600, 1800, or even 3000 kW.

This high total beam power is usually achieved by utilizing multipleaccelerating heads. For example, the electron beam device may includetwo, four, or more accelerating heads. The use of multiple heads, eachof which has a relatively low beam power, prevents excessive temperaturerise in the material, thereby preventing burning of the material, andalso increases the uniformity of the dose through the thickness of thelayer of material.

It is generally preferred that the bed of biomass material has arelatively uniform thickness. In some embodiments the thickness is lessthan about 1 inch (e.g., less than about 0.75 inches, less than about0.5 inches, less than about 0.25 inches, less than about 0.1 inches,between about 0.1 and 1 inch, between about 0.2 and 0.3 inches).

It is desirable to treat the material as quickly as possible. Ingeneral, it is preferred that treatment be performed at a dose rate ofgreater than about 0.25 Mrad per second, e.g., greater than about 0.5,0.75, 1, 1.5, 2, 5, 7, 10, 12, 15, or even greater than about 20 Mradper second, e.g., about 0.25 to 2 Mrad per second. Higher dose ratesallow a higher throughput for a target (e.g., the desired) dose. Higherdose rates generally require higher line speeds, to avoid thermaldecomposition of the material. In one implementation, the accelerator isset for 3 MeV, 50 mA beam current, and the line speed is 24 feet/minute,for a sample thickness of about 20 mm (e.g., comminuted corn cobmaterial with a bulk density of 0.5 g/cm3).

In some embodiments, electron bombardment is performed until thematerial receives a total dose of at least 0.1 Mrad, 0.25 Mrad, 1 Mrad,5 Mrad, e.g., at least 10, 20, 30 or at least 40 Mrad. In someembodiments, the treatment is performed until the material receives adose of from about 10 Mrad to about 50 Mrad, e.g., from about 20 Mrad toabout 40 Mrad, or from about 25 Mrad to about 30 Mrad. In someimplementations, a total dose of 25 to 35 Mrad is preferred, appliedideally over a couple of passes, e.g., at 5 Mrad/pass with each passbeing applied for about one second. Cooling methods, systems andequipment can be used before, during, after and in between radiations,for example utilizing a cooling screw conveyor and/or a cooled vibratoryconveyor.

Using multiple heads as discussed above, the material can be treated inmultiple passes, for example, two passes at 10 to 20 Mrad/pass, e.g., 12to 18 Mrad/pass, separated by a few seconds of cool-down, or threepasses of 7 to 12 Mrad/pass, e.g., 5 to 20 Mrad/pass, 10 to 40Mrad/pass, 9 to 11 Mrad/pass. As discussed herein, treating the materialwith several relatively low doses, rather than one high dose, tends toprevent overheating of the material and also increases dose uniformitythrough the thickness of the material. In some implementations, thematerial is stirred or otherwise mixed during or after each pass andthen smoothed into a uniform layer again before the next pass, tofurther enhance treatment uniformity.

In some embodiments, electrons are accelerated to, for example, a speedof greater than 75 percent of the speed of light, e.g., greater than 85,90, 95, or 99 percent of the speed of light.

In some embodiments, any processing described herein occurs onlignocellulosic material that remains dry as acquired or that has beendried, e.g., using heat and/or reduced pressure. For example, in someembodiments, the cellulosic and/or lignocellulosic material has lessthan about 25 wt. % retained water, measured at 25° C. and at fiftypercent relative humidity (e.g., less than about 20 wt. %, less thanabout 15 wt. %, less than about 14 wt. %, less than about 13 wt. %, lessthan about 12 wt. %, less than about 10 wt. %, less than about 9 wt. %,less than about 8 wt. %, less than about 7 wt. %, less than about 6 wt.%, less than about 5 wt. %, less than about 4 wt. %, less than about 3wt. %, less than about 2 wt. %, less than about 1 wt. %, or less thanabout 0.5 wt. %.

In some embodiments, two or more ionizing sources can be used, such astwo or more electron sources. For example, samples can be treated, inany order, with a beam of electrons, followed by gamma radiation and UVlight having wavelengths from about 100 nm to about 280 nm. In someembodiments, samples are treated with three ionizing radiation sources,such as a beam of electrons, gamma radiation, and energetic UV light.The biomass is conveyed through the treatment zone where it can bebombarded with electrons.

It may be advantageous to repeat the treatment to more thoroughly reducethe recalcitrance of the biomass and/or further modify the biomass. Inparticular the process parameters can be adjusted after a first (e.g.,second, third, fourth or more) pass depending on the recalcitrance ofthe material. In some embodiments, a conveyor can be used which includesa circular system where the biomass is conveyed multiple times throughthe various processes described above. In some other embodimentsmultiple treatment devices (e.g., electron beam generators) are used totreat the biomass multiple (e.g., 2, 3, 4 or more) times. In yet otherembodiments, a single electron beam generator may be the source ofmultiple beams (e.g., 2, 3, 4 or more beams) that can be used fortreatment of the biomass.

The effectiveness in changing the molecular/supermolecular structureand/or reducing the recalcitrance of the carbohydrate-containing biomassdepends on the electron energy used and the dose applied, while exposuretime depends on the power and dose. In some embodiments, the dose rateand total dose are adjusted so as not to destroy (e.g., char or burn)the biomass material. For example, the carbohydrates should not bedamaged in the processing so that they can be released from the biomassintact, e.g. as monomeric sugars.

In some embodiments, the treatment (with any electron source or acombination of sources) is performed until the material receives a doseof at least about 0.05 Mrad, e.g., at least about 0.1, 0.25, 0.5, 0.75,1.0, 2.5, 5.0, 7.5, 10.0, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100,125, 150, 175, or 200 Mrad. In some embodiments, the treatment isperformed until the material receives a dose of between 0.1-100 Mrad,1-200, 5-200, 10-200, 5-150, 50-150 Mrad, 5-100, 5-50, 5-40, 10-50,10-75, 15-50, 20-35 Mrad.

In some embodiments, relatively low doses of radiation are utilized,e.g., to increase the molecular weight of a cellulosic orlignocellulosic material (with any radiation source or a combination ofsources described herein). For example, a dose of at least about 0.05Mrad, e.g., at least about 0.1 Mrad or at least about 0.25, 0.5, 0.75.1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, or at least about 5.0 Mrad. In someembodiments, the irradiation is performed until the material receives adose of between 0.1 Mrad and 2.0 Mrad, e.g., between 0.5 rad and 4.0Mrad or between 1.0 Mrad and 3.0 Mrad.

It also can be desirable to irradiate from multiple directions,simultaneously or sequentially, in order to achieve a desired degree ofpenetration of radiation into the material. For example, depending onthe density and moisture content of the material, such as wood, and thetype of radiation source used (e.g., gamma or electron beam), themaximum penetration of radiation into the material may be only about0.75 inch. In such a cases, a thicker section (up to 1.5 inch) can beirradiated by first irradiating the material from one side, and thenturning the material over and irradiating from the other side.Irradiation from multiple directions can be particularly useful withelectron beam radiation, which irradiates faster than gamma radiationbut typically does not achieve as great a penetration depth.

Radiation Opaque Materials

As previously discussed, the invention can include processing thematerial in a vault and/or bunker that is constructed using radiationopaque materials. In some implementations, the radiation opaquematerials are selected to be capable of shielding the components fromX-rays with high energy (short wavelength), which can penetrate manymaterials. One important factor in designing a radiation shieldingenclosure is the attenuation length of the materials used, which willdetermine the required thickness for a particular material, blend ofmaterials, or layered structure. The attenuation length is thepenetration distance at which the radiation is reduced to approximately1/e (e=Euler's number) times that of the incident radiation. Althoughvirtually all materials are radiation opaque if thick enough, materialscontaining a high compositional percentage (e.g., density) of elementsthat have a high Z value (atomic number) have a shorter radiationattenuation length and thus if such materials are used a thinner,lighter shielding can be provided. Examples of high Z value materialsthat are used in radiation shielding are tantalum and lead. Anotherimportant parameter in radiation shielding is the halving distance,which is the thickness of a particular material that will reduce gammaray intensity by 50%. As an example for X-ray radiation with an energyof 0.1 MeV the halving thickness is about 15.1 mm for concrete and about2.7 mm for lead, while with an X-ray energy of 1 MeV the halvingthickness for concrete is about 44.45 mm and for lead is about 7.9 mm.Radiation opaque materials can be materials that are thick or thin solong as they can reduce the radiation that passes through to the otherside. Thus, if it is desired that a particular enclosure have a low wallthickness, e.g., for light weight or due to size constraints, thematerial chosen should have a sufficient Z value and/or attenuationlength so that its halving length is less than or equal to the desiredwall thickness of the enclosure.

In some cases, the radiation opaque material may be a layered material,for example, having a layer of a higher Z value material, to providegood shielding, and a layer of a lower Z value material to provide otherproperties (e.g., structural integrity, impact resistance, etc.). Insome cases, the layered material may be a “graded-Z” laminate, e.g.,including a laminate in which the layers provide a gradient from high-Zthrough successively lower-Z elements. In some cases the radiationopaque materials can be interlocking blocks, for example, lead and/orconcrete blocks can be supplied by NELCO Worldwide (Burlington, Mass.).For example, the blocks can include a dry-joint design so as to bereconfigurable and modular. For example, some materials that can be usedinclude concrete blocks, MEGASHILED™ MODULAR BLOCK, n-Series Lead Brick.For example, the radiation opaque materials can be high densitymaterials e.g., having densities greater than about 100 lbs/cu ft,greater than about 200 lbs for cu ft or even greater than about 300lb/cu ft. For example, NELCO (Burlington, Mass.) concrete blocks havingabout 147 lbs/cu ft, 250 lb/cu ft, 288 lb/cu ft and 300 lb/cu ft. Thematerials can be used to provide an entirely new construction or upgradeexisting facilities.

A radiation opaque material can reduce the radiation passing through astructure (e.g., a wall, door, ceiling, enclosure, a series of these orcombinations of these) formed of the material by about at least about10%, (e.g., at least about 20%, at least about 30%, at least about 40%,at least about 50%, at least about 60%, at least about 70%, at leastabout 80%, at least about 90%, at least about 95%, at least about 96%,at least about 97%, at least about 98%, at least about 99%, at leastabout 99.9%, at least about 99.99%, at least about 99.999%) as comparedto the incident radiation. Therefore, an enclosure made of a radiationopaque material can reduce the exposure of equipment/system/componentsby the same amount. Radiation opaque materials can include stainlesssteel, metals with Z values above 25 (e.g., lead, iron), concrete, dirt,sand and combinations thereof. Radiation opaque materials can include abarrier in the direction of the incident radiation of at least about 1mm (e.g., 5 mm, 10 mm, 5 cm, 10 cm, 100 cm, 1 m and even at least about10 m).

Radiation Sources

The type of radiation determines the kinds of radiation sources used aswell as the radiation devices and associated equipment. The methods,systems and equipment described herein, for example for treatingmaterials with radiation, can utilized sources as described herein aswell as any other useful source.

Sources of gamma rays include radioactive nuclei, such as isotopes ofcobalt, calcium, technetium, chromium, gallium, indium, iodine, iron,krypton, samarium, selenium, sodium, thallium, and xenon.

Sources of X-rays include electron beam collision with metal targets,such as tungsten or molybdenum or alloys, or compact light sources, suchas those produced commercially by Lyncean.

Alpha particles are identical to the nucleus of a helium atom and areproduced by the alpha decay of various radioactive nuclei, such asisotopes of bismuth, polonium, astatine, radon, francium, radium,several actinides, such as actinium, thorium, uranium, neptunium,curium, californium, americium, and plutonium.

Sources for ultraviolet radiation include deuterium or cadmium lamps.

Sources for infrared radiation include sapphire, zinc, or selenidewindow ceramic lamps.

Sources for microwaves include klystrons, Slevin type RF sources, oratom beam sources that employ hydrogen, oxygen, or nitrogen gases.

Accelerators used to accelerate the particles (e.g., electrons or ions)can be DC (e.g., electrostatic DC or electrodynamic DC), RF linear,magnetic induction linear or continuous wave. For example, variousirradiating devices may be used in the methods disclosed herein,including field ionization sources, electrostatic ion separators, fieldionization generators, thermionic emission sources, microwave dischargeion sources, recirculating or static accelerators, dynamic linearaccelerators, van de Graaff accelerators, Cockroft Walton accelerators(e.g., PELLETRON® accelerators), LINACS, Dynamitrons (e.g., DYNAMITRON®accelerators), cyclotrons, synchrotrons, betatrons, transformer-typeaccelerators, microtrons, plasma generators, cascade accelerators, andfolded tandem accelerators. For example, cyclotron type accelerators areavailable from IBA, Belgium, such as the RHODOTRON™ system, while DCtype accelerators are available from RDI, now IBA Industrial, such asthe DYNAMITRON®. Other suitable accelerator systems include, forexample: DC insulated core transformer (ICT) type systems, availablefrom Nissin High Voltage, Japan; S-band LINACs, available from L3-PSD(USA), Linac Systems (France), Mevex (Canada), and Mitsubishi HeavyIndustries (Japan); L-band LINACs, available from Iotron Industries(Canada); and ILU-based accelerators, available from Budker Laboratories(Russia). Ions and ion accelerators are discussed in IntroductoryNuclear Physics, Kenneth S. Krane, John Wiley & Sons, Inc. (1988), KrstoPrelec, FIZIKA B 6 (1997) 4, 177-206, Chu, William T., “Overview ofLight-Ion Beam Therapy”, Columbus-Ohio, ICRU-IAEA Meeting, 18-20 Mar.2006, Iwata, Y. et al., “Alternating-Phase-Focused 1H-DTL for Heavy-IonMedical Accelerators”, Proceedings of EPAC 2006, Edinburgh, Scotland,and Leitner, C. M. et al., “Status of the Superconducting ECR Ion SourceVenus”, Proceedings of EPAC 2000, Vienna, Austria. Some particleaccelerators and their uses are disclosed, for example, in U.S. Pat. No.7,931,784 to Medoff, the complete disclosure of which is incorporatedherein by reference.

Electrons may be produced by radioactive nuclei that undergo beta decay,such as isotopes of iodine, cesium, technetium, and iridium.Alternatively, an electron gun can be used as an electron source viathermionic emission and accelerated through an accelerating potential.An electron gun generates electrons, which are then accelerated througha large potential (e.g., greater than about 500 thousand, greater thanabout 1 million, greater than about 2 million, greater than about 5million, greater than about 6 million, greater than about 7 million,greater than about 8 million, greater than about 9 million, or evengreater than 10 million volts) and then scanned magnetically in the x-yplane, where the electrons are initially accelerated in the z directiondown the accelerator tube and extracted through a foil window. Scanningthe electron beams is useful for increasing the irradiation surface whenirradiating materials, e.g., a biomass, that is conveyed through thescanned beam. Scanning the electron beam also distributes the thermalload homogenously on the window and helps reduce the foil window rupturedue to local heating by the electron beam. Window foil rupture is acause of significant down-time due to subsequent necessary repairs andre-starting the electron gun.

Various other irradiating devices may be used in the methods disclosedherein, including field ionization sources, electrostatic ionseparators, field ionization generators, thermionic emission sources,microwave discharge ion sources, recirculating or static accelerators,dynamic linear accelerators, van de Graaff accelerators, and foldedtandem accelerators. Such devices are disclosed, for example, in U.S.Pat. No. 7,931,784 to Medoff, the complete disclosure of which isincorporated herein by reference.

A beam of electrons can be used as the radiation source. A beam ofelectrons has the advantages of high dose rates (e.g., 1, 5, or even 10Mrad per second), high throughput, less containment, and lessconfinement equipment. Electron beams can also have high electricalefficiency (e.g., 80%), allowing for lower energy usage relative toother radiation methods, which can translate into a lower cost ofoperation and lower greenhouse gas emissions corresponding to thesmaller amount of energy used. Electron beams can be generated, e.g., byelectrostatic generators, cascade generators, transformer generators,low energy accelerators with a scanning system, low energy acceleratorswith a linear cathode, linear accelerators, and pulsed accelerators.

Electrons can also be more efficient at causing changes in the molecularstructure of carbohydrate-containing materials, for example, by themechanism of chain scission. In addition, electrons having energies of0.5-10 MeV can penetrate low density materials, such as the biomassmaterials described herein, e.g., materials having a bulk density ofless than 0.5 g/cm³, and a depth of 0.3-10 cm. Electrons as an ionizingradiation source can be useful, e.g., for relatively thin piles, layersor beds of materials, e.g., less than about 0.5 inch, e.g., less thanabout 0.4 inch, 0.3 inch, 0.25 inch, or less than about 0.1 inch. Insome embodiments, the energy of each electron of the electron beam isfrom about 0.3 MeV to about 2.0 MeV (million electron volts), e.g., fromabout 0.5 MeV to about 1.5 MeV, or from about 0.7 MeV to about 1.25 MeV.Methods of irradiating materials are discussed in U.S. Pat. App. Pub.2012/0100577 A1, filed Oct. 18, 2011, the entire disclosure of which isherein incorporated by reference.

Electron beam irradiation devices may be procured commercially or built.For example elements or components such inductors, capacitors, casings,power sources, cables, wiring, voltage control systems, current controlelements, insulating material, microcontrollers and cooling equipmentcan be purchased and assembled into a device. Optionally, a commercialdevice can be modified and/or adapted. For example, devices andcomponents can be purchased from any of the commercial sources describedherein including Ion Beam Applications (Louvain-la-Neuve, Belgium),Wasik Associates Inc. (Dracut, Mass.), NHV Corporation (Japan), theTitan Corporation (San Diego, Calif.), Vivirad High Voltage Corp(Billerica, Mass.) and/or Budker Laboratories (Russia). Typical electronenergies can be 0.5 MeV, 1 MeV, 2 MeV, 4.5 MeV, 7.5 MeV, or 10 MeV.Typical electron beam irradiation device power can be 1 kW, 5 kW, 10 kW,20 kW, 50 kW, 60 kW, 70 kW, 80 kW, 90 kW, 100 kW, 125 kW, 150 kW, 175kW, 200 kW, 250 kW, 300 kW, 350 kW, 400 kW, 450 kW, 500 kW, 600 kW, 700kW, 800 kW, 900 kW or even 1000 kW. Accelerators that can be usedinclude NHV irradiators medium energy series EPS-500 (e.g., 500 kVaccelerator voltage and 65, 100 or 150 mA beam current), EPS-800 (e.g.,800 kV accelerator voltage and 65 or 100 mA beam current), or EPS-1000(e.g., 1000 kV accelerator voltage and 65 or 100 mA beam current). Also,accelerators from NHV's high energy series can be used such as EPS-1500(e.g., 1500 kV accelerator voltage and 65 mA beam current), EPS-2000(e.g., 2000 kV accelerator voltage and 50 mA beam current), EPS-3000(e.g., 3000 kV accelerator voltage and 50 mA beam current) and EPS-5000(e.g., 5000 and 30 mA beam current).

Tradeoffs in considering electron beam irradiation device powerspecifications include cost to operate, capital costs, depreciation, anddevice footprint. Tradeoffs in considering exposure dose levels ofelectron beam irradiation would be energy costs and environment, safety,and health (ESH) concerns. Typically, generators are housed in a vault,e.g., of lead or concrete, especially for production from X-rays thatare generated in the process. Tradeoffs in considering electron energiesinclude energy costs.

The electron beam irradiation device can produce either a fixed beam ora scanning beam. A scanning beam may be advantageous with large scansweep length and high scan speeds, as this would effectively replace alarge, fixed beam width. Further, available sweep widths of 0.5 m, 1 m,2 m or more are available. The scanning beam is preferred in mostembodiments described herein because of the larger scan width andreduced possibility of local heating and failure of the windows.

Electron Guns—Windows

The extraction system for an electron accelerator can include two windowfoils. The cooling gas in the two foil window extraction system can be apurge gas or a mixture, for example air, or a pure gas. In oneembodiment the gas is an inert gas such as nitrogen, argon, helium andor carbon dioxide. It is preferred to use a gas rather than a liquidsince energy losses to the electron beam are minimized. Mixtures of puregas can also be used, either pre-mixed or mixed in line prior toimpinging on the windows or in the space between the windows. Thecooling gas can be cooled, for example, by using a heat exchange system(e.g., a chiller) and/or by using boil off from a condensed gas (e.g.,liquid nitrogen, liquid helium). Window foils are described inPCT/US2013/64332 filed Oct. 10, 2013 the full disclosure of which isincorporated by reference herein.

Electron Guns—Beam Stops

In some embodiments the systems and methods include a beam stop (e.g., ashutter). For example, the beam stop can be used to quickly stop orreduce the irradiation of material without powering down the electronbeam device. Alternatively the beam stop can be used while powering upthe electron beam, e.g., the beam stop can stop the electron beam untila beam current of a desired level is achieved. The beam stop can beplaced between the primary foil window and a secondary foil window. Forexample, the beam stop can be mounted so that it is movable, that is, sothat it can be moved into and out of the beam path. Even partialcoverage of the beam can be used, for example, to control the dose ofirradiation. The beam stop can be mounted to the floor, to a conveyorfor the biomass, to a wall, to the radiation device (e.g., at the scanhorn), or to any structural support. Preferably the beam stop is fixedin relation to the scan horn so that the beam can be effectivelycontrolled by the beam stop. The beam stop can incorporate a hinge, arail, wheels, slots, or other means allowing for its operation in movinginto and out of the beam. The beam stop can be made of any material thatwill stop at least 5% of the electrons, e.g., at least 10%, 20%, 30%,40%, 50%, 60%, 70%, at least 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%,96%, 97%, 98%, 99% or even about 100% of the electrons.

The beam stop can be made of a metal including, but not limited to,stainless steel, lead, iron, molybdenum, silver, gold, titanium,aluminum, tin, or alloys of these, or laminates (layered materials) madewith such metals (e.g., metal-coated ceramic, metal-coated polymer,metal-coated composite, multilayered metal materials).

The beam stop can be cooled, for example, with a cooling fluid such asan aqueous solution or a gas. The beam stop can be partially orcompletely hollow, for example with cavities. Interior spaces of thebeam stop can be used for cooling fluids and gases. The beam stop can beof any shape, including flat, curved, round, oval, square, rectangular,beveled and wedged shapes.

The beam stop can have perforations so as to allow some electronsthrough, thus controlling (e.g., reducing) the levels of radiationacross the whole area of the window, or in specific regions of thewindow. The beam stop can be a mesh formed, for example, from fibers orwires. Multiple beam stops can be used, together or independently, tocontrol the irradiation. The beam stop can be remotely controlled, e.g.,by radio signal or hard wired to a motor for moving the beam into or outof position.

Beam Dumps

The embodiments disclosed herein can also include a beam dump whenutilizing a radiation treatment. A beam dump's purpose is to safelyabsorb a beam of charged particles. Like a beam stop, a beam dump can beused to block the beam of charged particles. However, a beam dump ismuch more robust than a beam stop, and is intended to block the fullpower of the electron beam for an extended period of time. They areoften used to block the beam as the accelerator is powering up.

Beam dumps are also designed to accommodate the heat generated by suchbeams, and are usually made from materials such as copper, aluminum,carbon, beryllium, tungsten, or mercury. Beam dumps can be cooled, forexample, using a cooling fluid that can be in thermal contact with thebeam dump.

Biomass Materials

Lignocellulosic materials include, but are not limited to, wood,particle board, forestry wastes (e.g., sawdust, aspen wood, wood chips),grasses, (e.g., switchgrass, miscanthus, cord grass, reed canary grass),grain residues, (e.g., rice hulls, oat hulls, wheat chaff, barleyhulls), agricultural waste (e.g., silage, canola straw, wheat straw,barley straw, oat straw, rice straw, jute, hemp, flax, bamboo, sisal,abaca, corn cobs, corn stover, soybean stover, corn fiber, alfalfa, hay,coconut hair), sugar processing residues (e.g., bagasse, beet pulp,agave bagasse), algae, seaweed, manure, sewage, and mixtures of any ofthese.

In some cases, the lignocellulosic material includes corncobs. Ground orhammermilled corncobs can be spread in a layer of relatively uniformthickness for irradiation, and after irradiation are easy to disperse inthe medium for further processing. To facilitate harvest and collection,in some cases the entire corn plant is used, including the corn stalk,corn kernels, and in some cases even the root system of the plant.

Advantageously, no additional nutrients (other than a nitrogen source,e.g., urea or ammonia) are required during fermentation of corncobs orcellulosic or lignocellulosic materials containing significant amountsof corncobs.

Corncobs, before and after comminution, are also easier to convey anddisperse, and have a lesser tendency to form explosive mixtures in airthan other cellulosic or lignocellulosic materials such as hay andgrasses.

Cellulosic materials include, for example, paper, paper products, paperwaste, paper pulp, pigmented papers, loaded papers, coated papers,filled papers, magazines, printed matter (e.g., books, catalogs,manuals, labels, calendars, greeting cards, brochures, prospectuses,newsprint), printer paper, polycoated paper, card stock, cardboard,paperboard, materials having a high α-cellulose content such as cotton,and mixtures of any of these. For example, paper products as describedin U.S. application Ser. No. 13/396,365 (“Magazine Feedstocks” by Medoffet al., filed Feb. 14, 2012), the full disclosure of which isincorporated herein by reference.

Cellulosic materials can also include lignocellulosic materials whichhave been partially or fully de-lignified.

In some instances other biomass materials can be utilized, for examplestarchy materials. Starchy materials include starch itself, e.g., cornstarch, wheat starch, potato starch or rice starch, a derivative ofstarch, or a material that includes starch, such as an edible foodproduct or a crop. For example, the starchy material can be arracacha,buckwheat, banana, barley, cassava, kudzu, ocra, sago, sorghum, regularhousehold potatoes, sweet potato, taro, yams, or one or more beans, suchas favas, lentils or peas. Blends of any two or more starchy materialsare also starchy materials. Mixtures of starchy, cellulosic and orlignocellulosic materials can also be used. For example, a biomass canbe an entire plant, a part of a plant or different parts of a plant,e.g., a wheat plant, cotton plant, a corn plant, rice plant or a tree.The starchy materials can be treated by any of the methods describedherein.

Microbial materials that can be used as feedstock can include, but arenot limited to, any naturally occurring or genetically modifiedmicroorganism or organism that contains or is capable of providing asource of carbohydrates (e.g., cellulose), for example, protists, e.g.,animal protists (e.g., protozoa such as flagellates, amoeboids,ciliates, and sporozoa) and plant protists (e.g., algae such alveolates,chlorarachniophytes, cryptomonads, euglenids, glaucophytes, haptophytes,red algae, stramenopiles, and viridaeplantae). Other examples includeseaweed, plankton (e.g., macroplankton, mesoplankton, microplankton,nanoplankton, picoplankton, and femptoplankton), phytoplankton, bacteria(e.g., gram positive bacteria, gram negative bacteria, andextremophiles), yeast and/or mixtures of these. In some instances,microbial biomass can be obtained from natural sources, e.g., the ocean,lakes, bodies of water, e.g., salt water or fresh water, or on land.Alternatively or in addition, microbial biomass can be obtained fromculture systems, e.g., large scale dry and wet culture and fermentationsystems.

In other embodiments, the biomass materials, such as cellulosic, starchyand lignocellulosic feedstock materials, can be obtained from transgenicmicroorganisms and plants that have been modified with respect to a wildtype variety. Such modifications may be, for example, through theiterative steps of selection and breeding to obtain desired traits in aplant. Furthermore, the plants can have had genetic material removed,modified, silenced and/or added with respect to the wild type variety.For example, genetically modified plants can be produced by recombinantDNA methods, where genetic modifications include introducing ormodifying specific genes from parental varieties, or, for example, byusing transgenic breeding wherein a specific gene or genes areintroduced to a plant from a different species of plant and/or bacteria.Another way to create genetic variation is through mutation breedingwherein new alleles are artificially created from endogenous genes. Theartificial genes can be created by a variety of ways including treatingthe plant or seeds with, for example, chemical mutagens (e.g., usingalkylating agents, epoxides, alkaloids, peroxides, formaldehyde),irradiation (e.g., X-rays, gamma rays, neutrons, beta particles, alphaparticles, protons, deuterons, UV radiation) and temperature shocking orother external stressing and subsequent selection techniques. Othermethods of providing modified genes is through error prone PCR and DNAshuffling followed by insertion of the desired modified DNA into thedesired plant or seed. Methods of introducing the desired geneticvariation in the seed or plant include, for example, the use of abacterial carrier, biolistics, calcium phosphate precipitation,electroporation, gene splicing, gene silencing, lipofection,microinjection and viral carriers. Additional genetically modifiedmaterials have been described in U.S. application Ser. No. 13/396,369filed Feb. 14, 2012 (published Feb. 28, 2013) the full disclosure ofwhich is incorporated herein by reference.

Any of the methods described herein can be practiced with mixtures ofany biomass materials described herein.

Other Materials

Other materials (e.g., natural or synthetic materials), for examplepolymers, can be treated and/or made utilizing the methods, equipmentand systems described hererin. For example polyethylene (e.g., linearlow density ethylene and high density polyethylene), polystyrenes,sulfonated polystyrenes, poly(vinyl chloride), polyesters (e.g., nylons,DACRON™, KODEL™), polyalkylene esters, poly vinyl esters, polyamides(e.g., KEVLAR™) polyethylene terephthalate, cellulose acetate, acetal,poly acrylonitrile, polycarbonates (e.g., LEXAN™), acrylics [e.g.,poly(methyl methacrylate), poly(methyl methacrylate),polyacrylnitriles], Poly urethanes, polypropylene, poly butadiene,polyisobutylene, polyacrylonitrile, polychloroprene (e.g. neoprene),poly(cis-1,4-isoprene) [e.g., natural rubber], poly(trans-1,4-isoprene)[e.g., gutta percha], phenol formaldehyde, melamine formaldehyde,epoxides, polyesters, poly amines, polycarboxylic acids, polylacticacids, polyvinyl alcohols, polyanhydrides, poly fluoro carbons (e.g.,TEFLON™), silicons (e.g., silicone rubber), polysilanes, poly ethers(e.g., polyethylene oxide, polypropylene oxide), waxes, oils andmixtures of these. Also included are plastics, rubbers, elastomers,fibers, waxes, gels, oils, adhesives, thermoplastics, thermosets,biodegradable polymers, resins made with these polymers, other polymers,other materials and combinations thereof. The polymers can be made byany useful method including cationic polymerization, anionicpolymerization, radical polymerization, metathesis polymerization, ringopening polymerization, graft polymerization, addition polymerization.In some cases the treatments disclosed herein can be used, for example,for radically initiated graft polymerization and cross linking.Composites of polymers, for example with glass, metals, biomass (e.g.,fibers, particles), ceramics can also be treated and/or made.

Other materials that can be treated by using the methods, systems andequipment disclosed herein are ceramic materials, minerals, metals,inorganic compounds. For example, silicon and germanium crystals,silicon nitrides, metal oxides, semiconductors, insulators, cements andor conductors.

In addition, manufactured multipart or shaped materials (e.g., molded,extruded, welded, riveted, layered or combined in any way) can betreated, for example cables, pipes, boards, enclosures, integratedsemiconductor chips, circuit boards, wires, tires, windows, laminatedmaterials, gears, belts, machines, combinations of these. For example,treating a material by the methods described herein can modify thesurfaces, for example, making them susceptible to furtherfunctionalization, combinations (e.g., welding) and/or treatment cancross link the materials.

Biomass Material Preparation—Mechanical Treatments

The biomass can be in a dry form, for example with less than about 35%moisture content (e.g., less than about 20%, less than about 15%, lessthan about 10% less than about 5%, less than about 4%, less than about3%, less than about 2% or even less than about 1%). The biomass can alsobe delivered in a wet state, for example as a wet solid, a slurry or asuspension with at least about 10 wt. % solids (e.g., at least about 20wt. %, at least about 30 wt. %, at least about 40 wt. %, at least about50 wt. %, at least about 60 wt. %, at least about 70 wt. %).

The processes disclosed herein can utilize low bulk density materials,for example cellulosic or lignocellulosic feedstocks that have beenphysically pretreated to have a bulk density of less than about 0.75g/cm3, e.g., less than about 0.7, 0.65, 0.60, 0.50, 0.35, 0.25, 0.20,0.15, 0.10, 0.05 or less, e.g., less than about 0.025 g/cm3. Bulkdensity is determined using ASTM D1895B. Briefly, the method involvesfilling a measuring cylinder of known volume with a sample and obtaininga weight of the sample. The bulk density is calculated by dividing theweight of the sample in grams by the known volume of the cylinder incubic centimeters. If desired, low bulk density materials can bedensified, for example, by methods described in U.S. Pat. No. 7,971,809to Medoff, the full disclosure of which is hereby incorporated byreference.

In some cases, the pre-treatment processing includes screening of thebiomass material. Screening can be through a mesh or perforated platewith a desired opening size, for example, less than about 6.35 mm (¼inch, 0.25 inch), (e.g., less than about 3.18 mm (⅛ inch, 0.125 inch),less than about 1.59 mm ( 1/16 inch, 0.0625 inch), is less than about0.79 mm ( 1/32 inch, 0.03125 inch), e.g., less than about 0.51 mm ( 1/50inch, 0.02000 inch), less than about 0.40 mm ( 1/64 inch, 0.015625inch), less than about 0.23 mm (0.009 inch), less than about 0.20 mm (1/128 inch, 0.0078125 inch), less than about 0.18 mm (0.007 inch), lessthan about 0.13 mm (0.005 inch), or even less than about 0.10 mm ( 1/256inch, 0.00390625 inch)). In one configuration, the desired biomass fallsthrough the perforations or screen and thus biomass larger than theperforations or screen are not irradiated. These larger materials can bere-processed, for example by comminuting, or they can simply be removedfrom processing. In another configuration material that is larger thanthe perforations is irradiated and the smaller material is removed bythe screening process or recycled. In this kind of a configuration, theconveyor itself (for example, a part of the conveyor) can be perforatedor made with a mesh. For example, in one particular embodiment thebiomass material may be wet and the perforations or mesh allow water todrain away from the biomass before irradiation.

Screening of material can also be by a manual method, for example, by anoperator or mechanoid (e.g., a robot equipped with a color, reflectivityor other sensor) that removes unwanted material. Screening can also beby magnetic screening wherein a magnet is disposed near the conveyedmaterial and the magnetic material is removed magnetically.

Optional pre-treatment processing can include heating the material. Forexample, a portion of a conveyor conveying the biomass or other materialcan be sent through a heated zone. The heated zone can be created, forexample, by IR radiation, microwaves, combustion (e.g., gas, coal, oil,biomass), resistive heating and/or inductive coils. The heat can beapplied from at least one side or more than one side, can be continuousor periodic and can be for only a portion of the material or all thematerial. For example, a portion of the conveying trough can be heatedby use of a heating jacket. Heating can be, for example, for the purposeof drying the material. In the case of drying the material, this canalso be facilitated, with or without heating, by the movement of a gas(e.g., air, oxygen, nitrogen, He, CO2, Argon) over and/or through thebiomass as it is being conveyed.

Optionally, pre-treatment processing can include cooling the material.Cooling material is described in U.S. Pat. No. 7,900,857 to Medoff, thedisclosure of which in incorporated herein by reference. For example,cooling can be by supplying a cooling fluid, for example water (e.g.,with glycerol), or nitrogen (e.g., liquid nitrogen) to the bottom of theconveying trough. Alternatively, a cooling gas, for example, chillednitrogen can be blown over the biomass materials or under the conveyingsystem.

Another optional pre-treatment processing method can include adding amaterial to the biomass or other feedstocks. The additional material canbe added by, for example, by showering, sprinkling and or pouring thematerial onto the biomass as it is conveyed. Materials that can be addedinclude, for example, metals, ceramics and/or ions as described in U.S.Pat. App. Pub. 2010/0105119 A1 (filed Oct. 26, 2009) and U.S. Pat. App.Pub. 2010/0159569 A1 (filed Dec. 16, 2009), the entire disclosures ofwhich are incorporated herein by reference. Optional materials that canbe added include acids and bases. Other materials that can be added areoxidants (e.g., peroxides, chlorates), polymers, polymerizable monomers(e.g., containing unsaturated bonds), water, catalysts, enzymes and/ororganisms. Materials can be added, for example, in pure form, as asolution in a solvent (e.g., water or an organic solvent) and/or as asolution. In some cases the solvent is volatile and can be made toevaporate e.g., by heating and/or blowing gas as previously described.The added material may form a uniform coating on the biomass or be ahomogeneous mixture of different components (e.g., biomass andadditional material). The added material can modulate the subsequentirradiation step by increasing the efficiency of the irradiation,damping the irradiation or changing the effect of the irradiation (e.g.,from electron beams to X-rays or heat). The method may have no impact onthe irradiation but may be useful for further downstream processing. Theadded material may help in conveying the material, for example, bylowering dust levels.

Biomass can be delivered to a conveyor (e.g., vibratory conveyors usedin the vaults herein described) by a belt conveyor, a pneumaticconveyor, a screw conveyor, a hopper, a pipe, manually or by acombination of these. The biomass can, for example, be dropped, pouredand/or placed onto the conveyor by any of these methods. In someembodiments the material is delivered to the conveyor using an enclosedmaterial distribution system to help maintain a low oxygen atmosphereand/or control dust and fines. Lofted or air suspended biomass fines anddust are undesirable because these can form an explosion hazard ordamage the window foils of an electron gun (if such a device is used fortreating the material).

The material can be leveled to form a uniform thickness between about0.0312 and 5 inches (e.g., between about 0.0625 and 2.000 inches,between about 0.125 and 1 inches, between about 0.125 and 0.5 inches,between about 0.3 and 0.9 inches, between about 0.2 and 0.5 inchesbetween about 0.25 and 1.0 inches, between about 0.25 and 0.5 inches,0.100+/−0.025 inches, 0.150+/−0.025 inches, 0.200+/−0.025 inches,0.250+/−0.025 inches, 0.300+/−0.025 inches, 0.350+/−0.025 inches,0.400+/−0.025 inches, 0.450+/−0.025 inches, 0.500+/−0.025 inches,0.550+/−0.025 inches, 0.600+/−0.025 inches, 0.700+/−0.025 inches,0.750+/−0.025 inches, 0.800+/−0.025 inches, 0.850+/−0.025 inches,0.900+/−0.025 inches, 0.900+/−0.025 inches.

Generally, it is preferred to convey the material as quickly as possiblethrough the electron beam to maximize throughput. For example thematerial can be conveyed at rates of at least 1 ft/min, e.g., at least 2ft/min, at least 3 ft/min, at least 4 ft/min, at least 5 ft/min, atleast 10 ft/min, at least 15 ft/min, 20, 25, 30, 35, 40, 45, 50 ft/min.The rate of conveying is related to the beam current, for example, for a¼ inch thick biomass and 100 mA, the conveyor can move at about 20ft/min to provide a useful irradiation dosage, at 50 mA the conveyor canmove at about 10 ft/min to provide approximately the same irradiationdosage.

After the biomass material has been conveyed through the radiation zone,optional post-treatment processing can be done. The optionalpost-treatment processing can, for example, be a process described withrespect to the pre-irradiation processing. For example, the biomass canbe screened, heated, cooled, and/or combined with additives. Uniquely topost-irradiation, quenching of the radicals can occur, for example,quenching of radicals by the addition of fluids or gases (e.g., oxygen,nitrous oxide, ammonia, liquids), using pressure, heat, and/or theaddition of radical scavengers. For example, the biomass can be conveyedout of the enclosed conveyor and exposed to a gas (e.g., oxygen) whereit is quenched, forming carboxylated groups. In one embodiment thebiomass is exposed during irradiation to the reactive gas or fluid.Quenching of biomass that has been irradiated is described in U.S. Pat.No. 8,083,906 to Medoff, the entire disclosure of which is incorporateherein by reference.

If desired, one or more mechanical treatments can be used in addition toirradiation to further reduce the recalcitrance of thecarbohydrate-containing material. These processes can be applied before,during and or after irradiation.

In some cases, the mechanical treatment may include an initialpreparation of the feedstock as received, e.g., size reduction ofmaterials, such as by comminution, e.g., cutting, grinding, shearing,pulverizing or chopping. For example, in some cases, loose feedstock(e.g., recycled paper, starchy materials, or switchgrass) is prepared byshearing or shredding. Mechanical treatment may reduce the bulk densityof the carbohydrate-containing material, increase the surface area ofthe carbohydrate-containing material and/or decrease one or moredimensions of the carbohydrate-containing material.

Alternatively, or in addition, the feedstock material can be treatedwith another treatment, for example chemical treatments, such as with anacid (HCl, H₂SO₄, H₃PO₄), a base (e.g., KOH and NaOH), a chemicaloxidant (e.g., peroxides, chlorates, ozone), irradiation, steamexplosion, pyrolysis, sonication, oxidation, chemical treatment. Thetreatments can be in any order and in any sequence and combinations. Forexample, the feedstock material can first be physically treated by oneor more treatment methods, e.g., chemical treatment including and incombination with acid hydrolysis (e.g., utilizing HCl, H₂SO₄, H₃PO₄),radiation, sonication, oxidation, pyrolysis or steam explosion, and thenmechanically treated. This sequence can be advantageous since materialstreated by one or more of the other treatments, e.g., irradiation orpyrolysis, tend to be more brittle and, therefore, it may be easier tofurther change the structure of the material by mechanical treatment. Asanother example, a feedstock material can be conveyed through ionizingradiation using a conveyor as described herein and then mechanicallytreated. Chemical treatment can remove some or all of the lignin (forexample chemical pulping) and can partially or completely hydrolyze thematerial. The methods also can be used with pre-hydrolyzed material. Themethods also can be used with material that has not been pre hydrolyzedThe methods can be used with mixtures of hydrolyzed and non-hydrolyzedmaterials, for example with about 50% or more non-hydrolyzed material,with about 60% or more non-hydrolyzed material, with about 70% or morenon-hydrolyzed material, with about 80% or more non-hydrolyzed materialor even with 90% or more non-hydrolyzed material

In addition to size reduction, which can be performed initially and/orlater in processing, mechanical treatment can also be advantageous for“opening up,” “stressing,” breaking or shattering thecarbohydrate-containing materials, making the cellulose of the materialsmore susceptible to chain scission and/or disruption of crystallinestructure during the physical treatment.

Methods of mechanically treating the carbohydrate-containing materialinclude, for example, milling or grinding. Milling may be performedusing, for example, a hammer mill, ball mill, colloid mill, conical orcone mill, disk mill, edge mill, Wiley mill, grist mill or other mill.Grinding may be performed using, for example, a cutting/impact typegrinder. Some exemplary grinders include stone grinders, pin grinders,coffee grinders, and bun grinders. Grinding or milling may be provided,for example, by a reciprocating pin or other element, as is the case ina pin mill. Other mechanical treatment methods include mechanicalripping or tearing, other methods that apply pressure to the fibers, andair attrition milling. Suitable mechanical treatments further includeany other technique that continues the disruption of the internalstructure of the material that was initiated by the previous processingsteps.

Mechanical feed preparation systems can be configured to produce streamswith specific characteristics such as, for example, specific maximumsizes, specific length-to-width, or specific surface areas ratios.Physical preparation can increase the rate of reactions, improve themovement of material on a conveyor, improve the irradiation profile ofthe material, improve the radiation uniformity of the material, orreduce the processing time required by opening up the materials andmaking them more accessible to processes and/or reagents, such asreagents in a solution.

The bulk density of feedstocks can be controlled (e.g., increased). Insome situations, it can be desirable to prepare a low bulk densitymaterial, e.g., by densifying the material (e.g., densification can makeit easier and less costly to transport to another site) and thenreverting the material to a lower bulk density state (e.g., aftertransport). The material can be densified, for example from less thanabout 0.2 g/cc to more than about 0.9 g/cc (e.g., less than about 0.3 tomore than about 0.5 g/cc, less than about 0.3 to more than about 0.9g/cc, less than about 0.5 to more than about 0.9 g/cc, less than about0.3 to more than about 0.8 g/cc, less than about 0.2 to more than about0.5 g/cc). For example, the material can be densified by the methods andequipment disclosed in U.S. Pat. No. 7,932,065 to Medoff andInternational Publication No. WO 2008/073186 (which was filed Oct. 26,2007, was published in English, and which designated the United States),the full disclosures of which are incorporated herein by reference.Densified materials can be processed by any of the methods describedherein, or any material processed by any of the methods described hereincan be subsequently densified.

In some embodiments, the material to be processed is in the form of afibrous material that includes fibers provided by shearing a fibersource. For example, the shearing can be performed with a rotary knifecutter.

For example, a fiber source, e.g., that is recalcitrant or that has hadits recalcitrance level reduced, can be sheared, e.g., in a rotary knifecutter, to provide a first fibrous material. The first fibrous materialis passed through a first screen, e.g., having an average opening sizeof 1.59 mm or less ( 1/16 inch, 0.0625 inch), provide a second fibrousmaterial. If desired, the fiber source can be cut prior to the shearing,e.g., with a shredder. For example, when a paper is used as the fibersource, the paper can be first cut into strips that are, e.g., ¼- to½-inch wide, using a shredder, e.g., a counter-rotating screw shredder,such as those manufactured by Munson (Utica, N.Y.). As an alternative toshredding, the paper can be reduced in size by cutting to a desired sizeusing a guillotine cutter. For example, the guillotine cutter can beused to cut the paper into sheets that are, e.g., 10 inches wide by 12inches long.

In some embodiments, the shearing of the fiber source and the passing ofthe resulting first fibrous material through a first screen areperformed concurrently. The shearing and the passing can also beperformed in a batch-type process.

For example, a rotary knife cutter can be used to concurrently shear thefiber source and screen the first fibrous material. A rotary knifecutter includes a hopper that can be loaded with a shredded fiber sourceprepared by shredding a fiber source.

In some implementations, the feedstock is physically treated prior tosaccharification and/or fermentation. Physical treatment processes caninclude one or more of any of those described herein, such as mechanicaltreatment, chemical treatment, irradiation, sonication, oxidation,pyrolysis or steam explosion. Treatment methods can be used incombinations of two, three, four, or even all of these technologies (inany order). When more than one treatment method is used, the methods canbe applied at the same time or at different times. Other processes thatchange a molecular structure of a biomass feedstock may also be used,alone or in combination with the processes disclosed herein.

Mechanical treatments that may be used, and the characteristics of themechanically treated carbohydrate-containing materials, are described infurther detail in U.S. Pat. App. Pub. 2012/0100577 A1, filed Oct. 18,2011, the full disclosure of which is hereby incorporated herein byreference.

Sonication, Pyrolysis, Oxidation, Steam Explosion

If desired, one or more sonication, pyrolysis, oxidative, or steamexplosion processes can be used instead of or in addition to irradiationto reduce or further reduce the recalcitrance of thecarbohydrate-containing material. For example, these processes can beapplied before, during and or after irradiation. These processes aredescribed in detail in U.S. Pat. No. 7,932,065 to Medoff, the fulldisclosure of which is incorporated herein by reference.

Intermediates and Products

Using the processes described herein, the biomass material can beconverted to one or more products, such as energy, fuels, foods andmaterials. For example, intermediates and products such as organicacids, salts of organic acids, anhydrides, esters of organic acids andfuels, e.g., fuels for internal combustion engines or feedstocks forfuel cells. Systems and processes are described herein that can use asfeedstock cellulosic and/or lignocellulosic materials that are readilyavailable, but often can be difficult to process, e.g., municipal wastestreams and waste paper streams, such as streams that include newspaper,Kraft paper, corrugated paper or mixtures of these.

Specific examples of products include, but are not limited to, hydrogen,sugars (e.g., glucose, xylose, arabinose, mannose, galactose, fructose,disaccharides, oligosaccharides and polysaccharides), alcohols (e.g.,monohydric alcohols or dihydric alcohols, such as ethanol, n-propanol,isobutanol, sec-butanol, tert-butanol or n-butanol), hydrated or hydrousalcohols (e.g., containing greater than 10%, 20%, 30% or even greaterthan 40% water), biodiesel, organic acids, hydrocarbons (e.g., methane,ethane, propane, isobutene, pentane, n-hexane, biodiesel, bio-gasolineand mixtures thereof), co-products (e.g., proteins, such as cellulolyticproteins (enzymes) or single cell proteins), and mixtures of any ofthese in any combination or relative concentration, and optionally incombination with any additives (e.g., fuel additives). Other examplesinclude carboxylic acids, salts of a carboxylic acid, a mixture ofcarboxylic acids and salts of carboxylic acids and esters of carboxylicacids (e.g., methyl, ethyl and n-propyl esters), ketones (e.g.,acetone), aldehydes (e.g., acetaldehyde), alpha and beta unsaturatedacids (e.g., acrylic acid) and olefins (e.g., ethylene). Other alcoholsand alcohol derivatives include propanol, propylene glycol,1,4-butanediol, 1,3-propanediol, sugar alcohols (e.g., erythritol,glycol, glycerol, sorbitol threitol, arabitol, ribitol, mannitol,dulcitol, fucitol, iditol, isomalt, maltitol, lactitol, xylitol andother polyols), and methyl or ethyl esters of any of these alcohols.Other products include methyl acrylate, methyl methacrylate, D-lacticacid, L-lactic acid, pyruvic acid, poly lactic acid, citric acid, formicacid, acetic acid, propionic acid, butyric acid, succinic acid, valericacid, caproic acid, 3-hydroxypropionic acid, palmitic acid, stearicacid, oxalic acid, malonic acid, glutaric acid, oleic acid, linoleicacid, glycolic acid, gamma-hydroxybutyric acid, and mixtures thereof,salts of any of these acids, mixtures of any of the acids and theirrespective salts.

Any combination of the above products with each other, and/or of theabove products with other products, which other products may be made bythe processes described herein or otherwise, may be packaged togetherand sold as products. The products may be combined, e.g., mixed, blendedor co-dissolved, or may simply be packaged or sold together.

Any of the products or combinations of products described herein may besanitized or sterilized prior to selling the products, e.g., afterpurification or isolation or even after packaging, to neutralize one ormore potentially undesirable contaminants that could be present in theproduct(s). Such sanitation can be done with electron bombardment, forexample, be at a dosage of less than about 20 Mrad, e.g., from about 0.1to 15 Mrad, from about 0.5 to 7 Mrad, or from about 1 to 3 Mrad.

The processes described herein can produce various by-product streamsuseful for generating steam and electricity to be used in other parts ofthe plant (co-generation) or sold on the open market. For example, steamgenerated from burning by-product streams can be used in a distillationprocess. As another example, electricity generated from burningby-product streams can be used to power electron beam generators used inpretreatment.

The by-products used to generate steam and electricity are derived froma number of sources throughout the process. For example, anaerobicdigestion of wastewater can produce a biogas high in methane and a smallamount of waste biomass (sludge). As another example,post-saccharification and/or post-distillate solids (e.g., unconvertedlignin, cellulose, and hemicellulose remaining from the pretreatment andprimary processes) can be used, e.g., burned, as a fuel.

Other intermediates and products, including food and pharmaceuticalproducts, are described in U.S. Pat. App. Pub. 2010/0124583 A1,published May 20, 2010, to Medoff, the full disclosure of which ishereby incorporated by reference herein.

Lignin Derived Products

The spent biomass (e.g., spent lignocellulosic material) fromlignocellulosic processing by the methods described are expected to havea high lignin content and in addition to being useful for producingenergy through combustion in a Co-Generation plant, may have uses asother valuable products. For example, the lignin can be used as capturedas a plastic, or it can be synthetically upgraded to other plastics. Insome instances, it can also be converted to lignosulfonates, which canbe utilized as binders, dispersants, emulsifiers or as sequestrants.

When used as a binder, the lignin or a lignosulfonate can, e.g., beutilized in coal briquettes, in ceramics, for binding carbon black, forbinding fertilizers and herbicides, as a dust suppressant, in the makingof plywood and particle board, for binding animal feeds, as a binder forfiberglass, as a binder in linoleum paste and as a soil stabilizer.

When used as a dispersant, the lignin or lignosulfonates can be used,e.g., concrete mixes, clay and ceramics, dyes and pigments, leathertanning and in gypsum board.

When used as an emulsifier, the lignin or lignosulfonates can be used,e.g., in asphalt, pigments and dyes, pesticides and wax emulsions.

When used as a sequestrant, the lignin or lignosulfonates can be used,e.g., in micro-nutrient systems, cleaning compounds and water treatmentsystems, e.g., for boiler and cooling systems.

For energy production lignin generally has a higher energy content thanholocellulose (cellulose and hemicellulose) since it contains morecarbon than homocellulose. For example, dry lignin can have an energycontent of between about 11,000 and 12,500 BTU per pound, compared to7,000 an 8,000 BTU per pound of holocellulose. As such, lignin can bedensified and converted into briquettes and pellets for burning. Forexample, the lignin can be converted into pellets by any methoddescribed herein. For a slower burning pellet or briquette, the lignincan be crosslinked, such as applying a radiation dose of between about0.5 Mrad and 5 Mrad. Crosslinking can make a slower burning form factor.The form factor, such as a pellet or briquette, can be converted to a“synthetic coal” or charcoal by pyrolyzing in the absence of air, e.g.,at between 400 and 950° C. Prior to pyrolyzing, it can be desirable tocrosslink the lignin to maintain structural integrity.

Saccharification

In order to convert the feedstock to a form that can be readilyprocessed, the glucan- or xylan-containing cellulose in the feedstockcan be hydrolyzed to low molecular weight carbohydrates, such as sugars,by a saccharifying agent, e.g., an enzyme or acid, a process referred toas saccharification. The low molecular weight carbohydrates can then beused, for example, in an existing manufacturing plant, such as a singlecell protein plant, an enzyme manufacturing plant, or a fuel plant,e.g., an ethanol manufacturing facility.

The feedstock can be hydrolyzed using an enzyme, e.g., by combining thematerials and the enzyme in a solvent, e.g., in an aqueous solution.

Alternatively, the enzymes can be supplied by organisms that break downbiomass, such as the cellulose and/or the lignin portions of thebiomass, contain or manufacture various cellulolytic enzymes(cellulases), ligninases or various small molecule biomass-degradingmetabolites. These enzymes may be a complex of enzymes that actsynergistically to degrade crystalline cellulose or the lignin portionsof biomass. Examples of cellulolytic enzymes include: endoglucanases,cellobiohydrolases, and cellobiases (beta-glucosidases).

During saccharification a cellulosic substrate can be initiallyhydrolyzed by endoglucanases at random locations producing oligomericintermediates. These intermediates are then substrates for exo-splittingglucanases such as cellobiohydrolase to produce cellobiose from the endsof the cellulose polymer. Cellobiose is a water-soluble 1,4-linked dimerof glucose. Finally, cellobiase cleaves cellobiose to yield glucose. Theefficiency (e.g., time to hydrolyze and/or completeness of hydrolysis)of this process depends on the recalcitrance of the cellulosic material.

Therefore, the treated biomass materials can be saccharified, generallyby combining the material and a cellulase enzyme in a fluid medium,e.g., an aqueous solution. In some cases, the material is boiled,steeped, or cooked in hot water prior to saccharification, as describedin U.S. Pat. App. Pub. 2012/0100577 A1 by Medoff and Masterman,published on Apr. 26, 2012, the entire contents of which areincorporated herein.

The saccharification process can be partially or completely performed ina tank (e.g., a tank having a volume of at least 4000, 40,000, or500,000 L) in a manufacturing plant, and/or can be partially orcompletely performed in transit, e.g., in a rail car, tanker truck, orin a supertanker or the hold of a ship. The time required for completesaccharification will depend on the process conditions and thecarbohydrate-containing material and enzyme used. If saccharification isperformed in a manufacturing plant under controlled conditions, thecellulose may be substantially entirely converted to sugar, e.g.,glucose in about 12-96 hours. If saccharification is performed partiallyor completely in transit, saccharification may take longer.

It is generally preferred that the tank contents be mixed duringsaccharification, e.g., using jet mixing as described in InternationalApp. No. PCT/US2010/035331, filed May 18, 2010, which was published inEnglish as WO 2010/135380 and designated the United States, the fulldisclosure of which is incorporated by reference herein.

The addition of surfactants can enhance the rate of saccharification.Examples of surfactants include non-ionic surfactants, such as a Tween®20 or Tween® 80 polyethylene glycol surfactants, ionic surfactants, oramphoteric surfactants.

It is generally preferred that the concentration of the sugar solutionresulting from saccharification be relatively high, e.g., greater than40%, or greater than 50, 60, 70, 80, 90 or even greater than 95% byweight. Water may be removed, e.g., by evaporation, to increase theconcentration of the sugar solution. This reduces the volume to beshipped, and also inhibits microbial growth in the solution.

Alternatively, sugar solutions of lower concentrations may be used, inwhich case it may be desirable to add an antimicrobial additive, e.g., abroad spectrum antibiotic, in a low concentration, e.g., 50 to 150 ppm.Other suitable antibiotics include amphotericin B, ampicillin,chloramphenicol, ciprofloxacin, gentamicin, hygromycin B, kanamycin,neomycin, penicillin, puromycin, streptomycin. Antibiotics will inhibitgrowth of microorganisms during transport and storage, and can be usedat appropriate concentrations, e.g., between 15 and 1000 ppm by weight,e.g., between 25 and 500 ppm, or between 50 and 150 ppm. If desired, anantibiotic can be included even if the sugar concentration is relativelyhigh. Alternatively, other additives with anti-microbial of preservativeproperties may be used. Preferably the antimicrobial additive(s) arefood-grade.

A relatively high concentration solution can be obtained by limiting theamount of water added to the carbohydrate-containing material with theenzyme. The concentration can be controlled, e.g., by controlling howmuch saccharification takes place. For example, concentration can beincreased by adding more carbohydrate-containing material to thesolution. In order to keep the sugar that is being produced in solution,a surfactant can be added, e.g., one of those discussed above.Solubility can also be increased by increasing the temperature of thesolution. For example, the solution can be maintained at a temperatureof 40-50° C., 60-80° C., or even higher.

Saccharifying Agents

Suitable cellulolytic enzymes include cellulases from species in thegenera Bacillus, Coprinus, Myceliophthora, Cephalosporium, Scytalidium,Penicillium, Aspergillus, Pseudomonas, Humicola, Fusarium, Thielavia,Acremonium, Chrysosporium and Trichoderma, especially those produced bya strain selected from the species Aspergillus (see, e.g., EP Pub. No. 0458 162), Humicola insolens (reclassified as Scytalidium thermophilum,see, e.g., U.S. Pat. No. 4,435,307), Coprinus cinereus, Fusariumoxysporum, Myceliophthora thermophila, Meripilus giganteus, Thielaviaterrestris, Acremonium sp. (including, but not limited to, A.persicinum, A. acremonium, A. brachypenium, A. dichromosporum, A.obclavatum, A. pinkertoniae, A. roseogriseum, A. incoloratum, and A.furatum). Preferred strains include Humicola insolens DSM 1800, Fusariumoxysporum DSM 2672, Myceliophthora thermophila CBS 117.65,Cephalosporium sp. RYM-202, Acremonium sp. CBS 478.94, Acremonium sp.CBS 265.95, Acremonium persicinum CBS 169.65, Acremonium acremonium AHU9519, Cephalosporium sp. CBS 535.71, Acremonium brachypenium CBS 866.73,Acremonium dichromosporum CBS 683.73, Acremonium obclavatum CBS 311.74,Acremonium pinkertoniae CBS 157.70, Acremonium roseogriseum CBS 134.56,Acremonium incoloratum CBS 146.62, and Acremonium furatum CBS 299.70H.Cellulolytic enzymes may also be obtained from Chrysosporium, preferablya strain of Chrysosporium lucknowense. Additional strains that can beused include, but are not limited to, Trichoderma (particularly T.viride, T. reesei, and T. koningii), alkalophilic Bacillus (see, forexample, U.S. Pat. No. 3,844,890 and EP Pub. No. 0 458 162), andStreptomyces (see, e.g., EP Pub. No. 0 458 162).

In addition to or in combination to enzymes, acids, bases and otherchemicals (e.g., oxidants) can be utilized to saccharify lignocellulosicand cellulosic materials. These can be used in any combination orsequence (e.g., before, after and/or during addition of an enzyme). Forexample, strong mineral acids can be utilized (e.g. HCl, H₂SO₄, H₃PO₄)and strong bases (e.g., NaOH, KOH).

Sugars

In the processes described herein, for example after saccharification,sugars (e.g., glucose and xylose) can be isolated. For example sugarscan be isolated by precipitation, crystallization, chromatography (e.g.,simulated moving bed chromatography, high pressure chromatography),centrifugation, extraction, any other isolation method known in the art,and combinations thereof.

Hydrogenation and Other Chemical Transformations

The processes described herein can include hydrogenation. For example,glucose and xylose can be hydrogenated to sorbitol and xylitolrespectively. Hydrogenation can be accomplished by use of a catalyst(e.g., Pt/gamma-Al₂O₃, Ru/C, Raney Nickel, or other catalysts know inthe art) in combination with H₂ under high pressure (e.g., 10 to 12000psi). Other types of chemical transformation of the products from theprocesses described herein can be used, for example, production oforganic sugar derived products such (e.g., furfural and furfural-derivedproducts). Chemical transformations of sugar derived products aredescribed in U.S. Ser. No. 13/934,704 filed Jul. 3, 2013, the entiredisclosure of which is incorporated herein by reference in its entirety.

Fermentation

Yeast and Zymomonas bacteria, for example, can be used for fermentationor conversion of sugar(s) to alcohol(s). Other microorganisms arediscussed below. The optimum pH for fermentations is about pH 4 to 7.For example, the optimum pH for yeast is from about pH 4 to 5, while theoptimum pH for Zymomonas is from about pH 5 to 6. Typical fermentationtimes are about 24 to 168 hours (e.g., 24 to 96 hrs) with temperaturesin the range of 20° C. to 40° C. (e.g., 26° C. to 40° C.), howeverthermophilic microorganisms prefer higher temperatures.

In some embodiments, e.g., when anaerobic organisms are used, at least aportion of the fermentation is conducted in the absence of oxygen, e.g.,under a blanket of an inert gas such as N2, Ar, He, CO2 or mixturesthereof. Additionally, the mixture may have a constant purge of an inertgas flowing through the tank during part of or all of the fermentation.In some cases, anaerobic condition, can be achieved or maintained bycarbon dioxide production during the fermentation and no additionalinert gas is needed.

In some embodiments, all or a portion of the fermentation process can beinterrupted before the low molecular weight sugar is completelyconverted to a product (e.g., ethanol). The intermediate fermentationproducts include sugar and carbohydrates in high concentrations. Thesugars and carbohydrates can be isolated via any means known in the art.These intermediate fermentation products can be used in preparation offood for human or animal consumption. Additionally or alternatively, theintermediate fermentation products can be ground to a fine particle sizein a stainless-steel laboratory mill to produce a flour-like substance.Jet mixing may be used during fermentation, and in some casessaccharification and fermentation are performed in the same tank.

Nutrients for the microorganisms may be added during saccharificationand/or fermentation, for example the food-based nutrient packagesdescribed in U.S. Pat. App. Pub. 2012/0052536, filed Jul. 15, 2011, thecomplete disclosure of which is incorporated herein by reference.

“Fermentation” includes the methods and products that are disclosed inapplication Nos. PCT/US2012/71093 published Jun. 27, 2013,PCT/US2012/71907 published Jun. 27, 2012, and PCT/US2012/71083 publishedJun. 27, 2012, the contents of which are incorporated by referenceherein in their entirety.

Mobile fermenters can be utilized, as described in International App.No. PCT/US2007/074028 (which was filed Jul. 20, 2007, was published inEnglish as WO 2008/011598 and designated the United States) and has aU.S. issued U.S. Pat. No. 8,318,453, the contents of which areincorporated herein in its entirety. Similarly, the saccharificationequipment can be mobile. Further, saccharification and/or fermentationmay be performed in part or entirely during transit.

Fermentation Agents

The microorganism(s) used in fermentation can be naturally-occurringmicroorganisms and/or engineered microorganisms. For example, themicroorganism can be a bacterium (including, but not limited to, e.g., acellulolytic bacterium), a fungus, (including, but not limited to, e.g.,a yeast), a plant, a protist, e.g., a protozoa or a fungus-like protest(including, but not limited to, e.g., a slime mold), or an alga. Whenthe organisms are compatible, mixtures of organisms can be utilized.

Suitable fermenting microorganisms have the ability to convertcarbohydrates, such as glucose, fructose, xylose, arabinose, mannose,galactose, oligosaccharides or polysaccharides into fermentationproducts. Fermenting microorganisms include strains of the genusSaccharomyces spp. (including, but not limited to, S. cerevisiae(baker's yeast), S. distaticus, S. uvarum), the genus Kluyveromyces,(including, but not limited to, K. marxianus, K. fragilis), the genusCandida (including, but not limited to, C. pseudotropicalis, and C.brassicae), Pichia stipitis (a relative of Candida shehatae), the genusClavispora (including, but not limited to, C. lusitaniae and C.opuntiae), the genus Pachysolen (including, but not limited to, P.tannophilus), the genus Bretannomyces (including, but not limited to,e.g., B. clausenii (Philippidis, G. P., 1996, Cellulose bioconversiontechnology, in Handbook on Bioethanol: Production and Utilization,Wyman, C. E., ed., Taylor & Francis, Washington, D.C., 179-212)). Othersuitable microorganisms include, for example, Zymomonas mobilis,Clostridium spp. (including, but not limited to, C. thermocellum(Philippidis, 1996, supra), C. saccharobutylacetonicum, C. tyrobutyricumC. saccharobutylicum, C. puniceum, C. beijernckii, and C.acetobutylicum), Moniliella spp. (including but not limited to M.pollinis, M. tomentosa, M. madida, M. nigrescens, M. oedocephali, M.megachiliensis), Yarrowia lipolytica, Aureobasidium sp.,Trichosporonoides sp., Trigonopsis variabilis, Trichosporon sp.,Moniliellaacetoabutans sp., Typhula variabilis, Candida magnoliae,Ustilaginomycetes sp., Pseudozyma tsukubaensis, yeast species of generaZygosaccharomyces, Debaryomyces, Hansenula and Pichia, and fungi of thedematioid genus Torula (e.g., T. corallina).

Additional microorganisms include the Lactobacillus group. Examplesinclude Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillusdelbrueckii, Lactobacillus plantarum, Lactobacillus coryniformis, e.g.,Lactobacillus coryniformis subspecies torquens, Lactobacillus pentosus,Lactobacillus brevis. Other microorganisms include Pediococuspenosaceus, Rhizopus oryzae.

Several organisms, such as bacteria, yeasts and fungi, can be utilizedto ferment biomass derived products such as sugars and alcohols tosuccinic acid and similar products. For example, organisms can beselected from; Actinobacillus succinogenes, Anaerobiospirillumsucciniciproducens, Mannheimia succiniciproducens, Ruminococcusflayerfaciens, Ruminococcus albus, Fibrobacter succinogenes, Bacteroidesfragilis, Bacteroides ruminicola, Bacteroides amylophilus, Bacteriodessuccinogenes, Mannheimia succiniciproducens, Corynebacterium glutamicum,Aspergillus niger, Aspergillus fumigatus, Byssochlamys nivea, Lentinusdegener, Paecilomyces varioti, Penicillium viniferum, Saccharomycescerevisiae, Enterococcus faecali, Prevotella ruminicolas, Debaryomyceshansenii, Candida catenulata VKM Y-5, C. mycoderma VKM Y-240, C. rugosaVKM Y-67, C. paludigena VKM Y-2443, C. utilis VKM Y-74, C. utilis 766,C. zeylanoides VKM Y-6, C. zeylanoides VKM Y-14, C. zeylanoides VKMY-2324, C. zeylanoides VKM Y-1543, C. zeylanoides VKM Y-2595, C. validaVKM Y-934, Kluyveromyces wickerhamii VKM Y-589, Pichia anomala VKMY-118, P. besseyi VKM Y-2084, P. media VKM Y-1381, P. guilliermondiiH-P-4, P. guilliermondii 916, P. inositovora VKM Y-2494, Saccharomycescerevisiae VKM Y-381, Torulopsis candida 127, T. candida 420, Yarrowialipolytica 12a, Y. lipolytica VKM Y-47, Y. lipolytica 69, Y. lipolyticaVKM Y-57, Y. lipolytica 212, Y. lipolytica 374/4, Y. lipolytica 585, Y.lipolytica 695, Y. lipolytica 704, and mixtures of these organisms.

Many such microbial strains are publicly available, either commerciallyor through depositories such as the ATCC (American Type CultureCollection, Manassas, Va., USA), the NRRL (Agricultural Research ServiceCulture Collection, Peoria, Ill., USA), or the DSMZ (Deutsche Sammlungvon Mikroorganismen and Zellkulturen GmbH, Braunschweig, Germany), toname a few.

Commercially available yeasts include, for example, RED STAR®/LesaffreEthanol Red (available from Red Star/Lesaffre, USA), FALK) (availablefrom Fleischmann's Yeast, a division of Burns Philip Food Inc., USA),SUPERSTART® (available from Alltech, now Lalemand), GERT STRAND®(available from Gert Strand AB, Sweden) and FERMOL® (available from DSMSpecialties).

Distillation

After fermentation, the resulting fluids can be distilled using, forexample, a “beer column” to separate ethanol and other alcohols from themajority of water and residual solids. The vapor exiting the beer columncan be, e.g., 35% by weight ethanol and can be fed to a rectificationcolumn. A mixture of nearly azeotropic (92.5%) ethanol and water fromthe rectification column can be purified to pure (99.5%) ethanol usingvapor-phase molecular sieves. The beer column bottoms can be sent to thefirst effect of a three-effect evaporator. The rectification columnreflux condenser can provide heat for this first effect. After the firsteffect, solids can be separated using a centrifuge and dried in a rotarydryer. A portion (25%) of the centrifuge effluent can be recycled tofermentation and the rest sent to the second and third evaporatoreffects. Most of the evaporator condensate can be returned to theprocess as fairly clean condensate with a small portion split off towaste water treatment to prevent build-up of low-boiling compounds.

Hydrocarbon—Containing Materials

In other embodiments utilizing the methods and systems described herein,hydrocarbon-containing materials can be processed. Any process describedherein can be used to treat any hydrocarbon-containing material hereindescribed. “Hydrocarbon-containing materials,” as used herein, is meantto include oil sands, oil shale, tar sands, coal dust, coal slurry,bitumen, various types of coal, and other naturally-occurring andsynthetic materials that include both hydrocarbon components and solidmatter. The solid matter can include rock, sand, clay, stone, silt,drilling slurry, or other solid organic and/or inorganic matter. Theterm can also include waste products such as drilling waste andby-products, refining waste and by-products, or other waste productscontaining hydrocarbon components, such as asphalt shingling andcovering, asphalt pavement, etc.

In yet other embodiments utilizing the methods and systems describedherein, wood and wood containing produces can be processed. For examplelumber products can be processed, e.g. boards, sheets, laminates, beams,particle boards, composites, rough cut wood, soft wood and hard wood. Inaddition cut trees, bushes, wood chips, saw dust, roots, bark, stumps,decomposed wood and other wood containing biomass material can beprocessed.

Conveying Systems

Various conveying systems can be used to convey the biomass material,for example, as discussed, to a vault, and under an electron beam in avault. Exemplary conveyors are belt conveyors, pneumatic conveyors,screw conveyors, carts, trains, trains or carts on rails, elevators,front loaders, backhoes, cranes, various scrapers and shovels, trucks,and throwing devices can be used. For example, vibratory conveyors canbe used in various processes described herein. Vibratory conveyors aredescribed in PCT/US2013/64289 filed Oct. 10, 2013 the full disclosure ofwhich is incorporated by reference herein.

Vibratory conveyors are particularly useful for spreading the materialand producing a uniform layer on the conveyor trough surface. Forexample the initial feedstock can form a pile of material that can be atleast four feet high (e.g., at least about 3 feet, at least about 2feet, at least about 1 foot, at least about 6 inches, at least about 5inches, at least about, 4 inches, at least about 3 inches, at leastabout 2 inches, at least about 1 inch, at least about ½ inch) and spansless than the width of the conveyor (e.g., less than about 10%, lessthan about 20%, less than about 30%, less than about 40%, less thanabout 50%, less than about 60%, less than about 70%, less than about80%, less than about 90%, less than about 95%, less than about 99%). Thevibratory conveyor can spread the material to span the entire width ofthe conveyor trough and have a uniform thickness, preferably asdiscussed above. In some cases, an additional spreading method can beuseful. For example, a spreader such as a broadcast spreader, a dropspreader (e.g., a CHRISTY SPREADER™) or combinations thereof can be usedto drop (e.g., place, pour, spill and/or sprinkle) the feedstock over awide area. Optionally, the spreader can deliver the biomass as a wideshower or curtain onto the vibratory conveyor. Additionally, a secondconveyor, upstream from the first conveyor (e.g., the first conveyor isused in the irradiation of the feedstock), can drop biomass onto thefirst conveyor, where the second conveyor can have a width transverse tothe direction of conveying smaller than the first conveyor. Inparticular, when the second conveyor is a vibratory conveyor, thefeedstock is spread by the action of the second and first conveyor. Insome optional embodiments, the second conveyor ends in a bias cross cutdischarge (e.g., a bias cut with a ratio of 4:1) so that the materialcan be dropped as a wide curtain (e.g., wider than the width of thesecond conveyor) onto the first conveyor. The initial drop area of thebiomass by the spreader (e.g., broadcast spreader, drop spreader,conveyor, or cross cut vibratory conveyor) can span the entire width ofthe first vibratory conveyor, or it can span part of this width. Oncedropped onto the conveyor, the material is spread even more uniformly bythe vibrations of the conveyor so that, preferably, the entire width ofthe conveyor is covered with a uniform layer of biomass. In someembodiments combinations of spreaders can be used. Some methods ofspreading a feed stock are described in U.S. Pat. No. 7,153,533, filedJul. 23, 2002 and published Dec. 26, 2006, the entire disclosure ofwhich is incorporated herein by reference.

Generally, it is preferred to convey the material as quickly as possiblethrough an electron beam to maximize throughput. For example, thematerial can be conveyed at rates of at least 1 ft/min, e.g., at least 2ft/min, at least 3 ft/min, at least 4 ft/min, at least 5 ft/min, atleast 10 ft/min, at least 15 ft/min, at least 20 ft/min, at least 25ft/min, at least 30 ft/min, at least 40 ft/min, at least 50 ft/min, atleast 60 ft/min, at least 70 ft/min, at least 80 ft/min, at least 90ft/min. The rate of conveying is related to the beam current andtargeted irradiation dose, for example, for a ¼ inch thick biomassspread over a 5.5 foot wide conveyor and 100 mA, the conveyor can moveat about 20 ft/min to provide a useful irradiation dosage (e.g. about 10Mrad for a single pass), at 50 mA the conveyor can move at about 10ft/min to provide approximately the same irradiation dosage.

The rate at which material can be conveyed depends on the shape and massof the material being conveyed, and the desired treatment. Flowingmaterials e.g., particulate materials, are particularly amenable toconveying with vibratory conveyors. Conveying speeds can, for examplebe, at least 100 lb/hr (e.g., at least 500 lb/hr, at least 1000 lb/hr,at least 2000 lb/hr, at least 3000 lb/hr, at least 4000 lb/hr, at least5000 lb/hr, at least 10,000 lb/hr, at least 15,000 lb/hr, or even atleast 25,000 lb/hr). Some typical conveying speeds can be between about1000 and 10,000 lb/hr, (e.g., between about 1000 lb/hr and 8000 lb/hr,between about 2000 and 7000 lb/hr, between about 2000 and 6000 lb/hr,between about 2000 and 5000 lb/hr, between about 2000 and 4500 lb/hr,between about 1500 and 5000 lb/hr, between about 3000 and 7000 lb/hr,between about 3000 and 6000 lb/hr, between about 4000 and 6000 lb/hr andbetween about 4000 and 5000 lb/hr). Typical conveying speeds depend onthe density of the material. For example, for a biomass with a densityof about 35 lb/ft3, and a conveying speed of about 5000 lb/hr, thematerial is conveyed at a rate of about 143 ft3/hr, if the material is¼″ thick and is in a trough 5.5 ft wide, the material is conveyed at arate of about 1250 ft/hr (about 21 ft/min). Rates of conveying thematerial can therefore vary greatly. Preferably, for example, a ¼″ thicklayer of biomass, is conveyed at speeds of between about 5 and 100ft/min (e.g. between about 5 and 100 ft/min, between about 6 and 100ft/min, between about 7 and 100 ft/min, between about 8 and 100 ft/min,between about 9 and 100 ft/min, between about 10 and 100 ft/min, betweenabout 11 and 100 ft/min, between about 12 and 100 ft/min, between about13 and 100 ft/min, between about 14 and 100 ft/min, between about 15 and100 ft/min, between about 20 and 100 ft/min, between about 30 and 100ft/min, between about 40 and 100 ft/min, between about 2 and 60 ft/min,between about 3 and 60 ft/min, between about 5 and 60 ft/min, betweenabout 6 and 60 ft/min, between about 7 and 60 ft/min, between about 8and 60 ft/min, between about 9 and 60 ft/min, between about 10 and 60ft/min, between about 15 and 60 ft/min, between about 20 and 60 ft/min,between about 30 and 60 ft/min, between about 40 and 60 ft/min, betweenabout 2 and 50 ft/min, between about 3 and 50 ft/min, between about 5and 50 ft/min, between about 6 and 50 ft/min, between about 7 and 50ft/min, between about 8 and 50 ft/min, between about 9 and 50 ft/min,between about 10 and 50 ft/min, between about 15 and 50 ft/min, betweenabout 20 and 50 ft/min, between about 30 and 50 ft/min, between about 40and 50 ft/min). It is preferable that the material be conveyed at aconstant rate, for example, to help maintain a constant irradiation ofthe material as it passes under the electron beam (e.g., shower, field).

The vibratory conveyors described can include screens used for sievingand sorting materials. Port openings on the side or bottom of thetroughs can be used for sorting, selecting or removing specificmaterials, for example, by size or shape. Some conveyors havecounterbalances to reduce the dynamic forces on the support structure.Some vibratory conveyors are configured as spiral elevators, aredesigned to curve around surfaces and/or are designed to drop materialfrom one conveyor to another (e.g., in a step, cascade or as a series ofsteps or a stair). Along with conveying materials conveyors can be used,by themselves or coupled with other equipment or systems, for screening,separating, sorting, classifying, distributing, sizing, inspection,picking, metal removing, freezing, blending, mixing, orienting, heating,cooking, drying, dewatering, cleaning, washing, leaching, quenching,coating, de-dusting and/or feeding. The conveyors can also includecovers (e.g., dust-tight covers), side discharge gates, bottom dischargegates, special liners (e.g., anti-stick, stainless steel, rubber, customsteal, and or grooved), divided troughs, quench pools, screens,perforated plates, detectors (e.g., metal detectors), high temperaturedesigns, food grade designs, heaters, dryers and or coolers. Inaddition, the trough can be of various shapes, for example, flatbottomed, vee shaped bottom, flanged at the top, curved bottom, flatwith ridges in any direction, tubular, half pipe, covered or anycombinations of these. In particular, the conveyors can be coupled withan irradiation systems and/or equipment.

The conveyors (e.g., vibratory conveyor) can be made of corrosionresistant materials. The conveyors can utilize structural materials thatinclude stainless steel (e.g., 304, 316 stainless steel, HASTELLOY®ALLOYS and INCONEL® Alloys). For example, HASTELLOY® Corrosion-Resistantalloys from Hynes (Kokomo, Ind., USA) such as HASTELLOY® B-3® ALLOY,HASTELLOY® HYBRID-BC1® ALLOY, HASTELLOY® C-4 ALLOY, HASTELLOY® C-22®ALLOY, HASTELLOY® C-22HS® ALLOY, HASTELLOY® C-276 ALLOY, HASTELLOY®C-2000® ALLOY, HASTELLOY® G-30® ALLOY, HASTELLOY® G-35® ALLOY,HASTELLOY® N ALLOY and HASTELLOY® ULTIMET® alloy.

The vibratory conveyors can include non-stick release coatings, forexample, TUFFLON™ (Dupont, Del., USA). The vibratory conveyors can alsoinclude corrosion resistant coatings. For example, coatings that can besupplied from Metal Coatings Corp (Houston, Tex., USA) and others suchas Fluoropolymer, XYLAN®, Molybdenum Disulfide, Epoxy Phenolic,Phosphate-ferrous metal coating, Polyurethane-high gloss topcoat forepoxy, inorganic zinc, Poly Tetrafluoro ethylene, PPS/RYTON®,fluorinated ethylene propylene, PVDF/DYKOR®, ECTFE/HALAR® and CeramicEpoxy Coating. The coatings can improve resistance to process gases(e.g., ozone), chemical corrosion, pitting corrosion, galling corrosionand oxidation.

Optionally, in addition to the conveying systems described herein, oneor more other conveying systems can be enclosed. When using anenclosure, the enclosed conveyor can also be purged with an inert gas soas to maintain an atmosphere at a reduced oxygen level. Keeping oxygenlevels low avoids the formation of ozone which in some instances isundesirable due to its reactive and toxic nature. For example, theoxygen can be less than about 20% (e.g., less than about 10%, less thanabout 1%, less than about 0.1%, less than about 0.01%, or even less thanabout 0.001% oxygen). Purging can be done with an inert gas including,but not limited to, nitrogen, argon, helium or carbon dioxide. This canbe supplied, for example, from a boil off of a liquid source (e.g.,liquid nitrogen or helium), generated or separated from air in situ, orsupplied from tanks. The inert gas can be recirculated and any residualoxygen can be removed using a catalyst, such as a copper catalyst bed.Alternatively, combinations of purging, recirculating and oxygen removalcan be done to keep the oxygen levels low.

The enclosed conveyor can also be purged with a reactive gas that canreact with the biomass. This can be done before, during or after theirradiation process. The reactive gas can be, but is not limited to,nitrous oxide, ammonia, oxygen, ozone, hydrocarbons, aromatic compounds,amides, peroxides, azides, halides, oxyhalides, phosphides, phosphines,arsines, sulfides, thiols, boranes and/or hydrides. The reactive gas canbe activated in the enclosure, e.g., by irradiation (e.g., electronbeam, UV irradiation, microwave irradiation, heating, IR radiation), sothat it reacts with the biomass. The biomass itself can be activated,for example by irradiation. Preferably the biomass is activated by theelectron beam, to produce radicals which then react with the activatedor unactivated reactive gas, e.g., by radical coupling or quenching.

Purging gases supplied to an enclosed conveyor can also be cooled, forexample below about 25° C., below about 0° C., below about −40° C.,below about −80° C., below about −120° C. For example, the gas can beboiled off from a compressed gas such as liquid nitrogen or sublimedfrom solid carbon dioxide. As an alternative example, the gas can becooled by a chiller or part of or the entire conveyor can be cooled.

Other Embodiments

Any material, processes or processed materials disclosed herein can beused to make products and/or intermediates such as composites, fillers,binders, plastic additives, adsorbents and controlled release agents.The methods can include densification, for example, by applying pressureand heat to the materials. For example composites can be made bycombining fibrous materials with a resin or polymer. For example,radiation cross-linkable resin, e.g., a thermoplastic resin can becombined with a fibrous material to provide a fibrousmaterial/cross-linkable resin combination. Such materials can be, forexample, useful as building materials, protective sheets, containers andother structural materials (e.g., molded and/or extruded products).Absorbents can be, for example, in the form of pellets, chips, fibersand/or sheets. Adsorbents can be used, for example, as pet bedding,packaging material or in pollution control systems. Controlled releasematrices can also be the form of, for example, pellets, chips, fibersand or sheets. The controlled release matrices can, for example, be usedto release drugs, biocides, fragrances. For example, composites,absorbents and control release agents and their uses are described inInternational Serial No. PCT/US2006/010648, filed Mar. 23, 2006, andU.S. Pat. No. 8,074,910 filed Nov. 22, 2011, the entire disclosures ofwhich are herein incorporated by reference.

In some instances, the biomass material is treated at a first level toreduce recalcitrance, e.g., utilizing accelerated electrons, toselectively release one or more sugars (e.g., xylose). The biomass canthen be treated to a second level to release one or more other sugars(e.g., glucose). Optionally, the biomass can be dried betweentreatments. The treatments can include applying chemical and biochemicaltreatments to release the sugars. For example, a biomass material can betreated to a level of less than about 20 Mrad (e.g., less than about 15Mrad, less than about 10 Mrad, less than about 5 Mrad, less than about 2Mrad) and then treated with a solution of sulfuric acid, containing lessthan 10% sulfuric acid (e.g., less than about 9%, less than about 8%,less than about 7%, less than about 6%, less than about 5%, less thanabout 4%, less than about 3%, less than about 2%, less than about 1%,less than about 0.75%, less than about 0.50%, less than about 0.25%) torelease xylose. Xylose, for example that is released into solution, canbe separated from solids and optionally the solids washed with asolvent/solution (e.g., with water and/or acidified water). Optionally,the solids can be dried, for example, in air and/or under vacuumoptionally with heating (e.g., below about 150 deg C., below about 120deg C.) to a water content below about 25 wt % (below about 20 wt. %,below about 15 wt. %, below about 10 wt. %, below about 5 wt. %). Thesolids can then be treated with a level of less than about 30 Mrad(e.g., less than about 25 Mrad, less than about 20 Mrad, less than about15 Mrad, less than about 10 Mrad, less than about 5 Mrad, less thanabout 1 Mrad or even not at all) and then treated with an enzyme (e.g.,a cellulase) to release glucose. The glucose (e.g., glucose in solution)can be separated from the remaining solids. The solids can then befurther processed, for example, utilized to make energy or otherproducts (e.g., lignin derived products).

Flavors, Fragrances and Colorants

Any of the products and/or intermediates described herein, for example,produced by the processes, systems and/or equipment described herein,can be combined with flavors, fragrances, colorants and/or mixtures ofthese. For example, any one or more of (optionally along with flavors,fragrances and/or colorants) sugars, organic acids, fuels, polyols, suchas sugar alcohols, biomass, fibers and composites can be combined with(e.g., formulated, mixed or reacted) or used to make other products. Forexample, one or more such product can be used to make soaps, detergents,candies, drinks (e.g., cola, wine, beer, liquors such as gin or vodka,sports drinks, coffees, teas), syrups, pharmaceuticals, adhesives,sheets (e.g., woven, none woven, filters, tissues) and/or composites(e.g., boards). For example, one or more such product can be combinedwith herbs, flowers, petals, spices, vitamins, potpourri, or candles.For example, the formulated, mixed or reacted combinations can haveflavors/fragrances of grapefruit, orange, apple, raspberry, banana,lettuce, celery, cinnamon, chocolate, vanilla, peppermint, mint, onion,garlic, pepper, saffron, ginger, milk, wine, beer, tea, lean beef, fish,clams, olive oil, coconut fat, pork fat, butter fat, beef bouillon,legume, potatoes, marmalade, ham, coffee and cheeses.

Flavors, fragrances and colorants can be added in any amount, such asbetween about 0.001 wt. % to about 30 wt. %, e.g., between about 0.01 toabout 20, between about 0.05 to about 10, or between about 0.1 wt. % toabout 5 wt. %. These can be formulated, mixed and or reacted (e.g., withany one of more product or intermediate described herein) by any meansand in any order or sequence (e.g., agitated, mixed, emulsified, gelled,infused, heated, sonicated, and/or suspended). Fillers, binders,emulsifier, antioxidants can also be utilized, for example, proteingels, starches and silica.

In one embodiment the flavors, fragrances and colorants can be added tothe biomass immediately after the biomass is irradiated such that thereactive sites created by the irradiation may react with reactivecompatible sites of the flavors, fragrances, and colorants.

The flavors, fragrances and colorants can be natural and/or syntheticmaterials. These materials can be one or more of a compound, acomposition or mixtures of these (e.g., a formulated or naturalcomposition of several compounds). Optionally the flavors, fragrances,antioxidants and colorants can be derived biologically, for example,from a fermentation process (e.g., fermentation of saccharifiedmaterials as described herein). Alternatively, or additionally theseflavors, fragrances and colorants can be harvested from a whole organism(e.g., plant, fungus, animal, bacteria or yeast) or a part of anorganism. The organism can be collected and or extracted to providecolor, flavors, fragrances and/or antioxidant by any means includingutilizing the methods, systems and equipment described herein, hot waterextraction, supercritical fluid extraction, chemical extraction (e.g.,solvent or reactive extraction including acids and bases), mechanicalextraction (e.g., pressing, comminuting, filtering), utilizing anenzyme, utilizing a bacteria such as to break down a starting material,and combinations of these methods. The compounds can be derived by achemical reaction, for example, the combination of a sugar (e.g., asproduced as described herein) with an amino acid (Maillard reaction).The flavor, fragrance, antioxidant and/or colorant can be anintermediate and or product produced by the methods, equipment orsystems described herein, for example and ester and a lignin derivedproduct.

Some examples of flavor, fragrances or colorants are polyphenols.Polyphenols are pigments responsible for the red, purple and bluecolorants of many fruits, vegetables, cereal grains, and flowers.Polyphenols also can have antioxidant properties and often have a bittertaste. The antioxidant properties make these important preservatives. Onclass of polyphenols are the flavonoids, such as Anthocyanidines,flavanonols, flavan-3-ols, flavanones and flavanonols. Other phenoliccompounds that can be used include phenolic acids and their esters, suchas chlorogenic acid and polymeric tannins.

Among the colorants inorganic compounds, minerals or organic compoundscan be used, for example, titanium dioxide, zinc oxide, aluminum oxide,cadmium yellow (E.g., CdS), cadmium orange (e.g., CdS with some Se),alizarin crimson (e.g., synthetic or non-synthetic rose madder),ultramarine (e.g., synthetic ultramarine, natural ultramarine, syntheticultramarine violet), cobalt blue, cobalt yellow, cobalt green, viridian(e.g., hydrated chromium(III)oxide), chalcophylite, conichalcite,cornubite, cornwallite and liroconite. Black pigments such as carbonblack and self-dispersed blacks may be used.

Some flavors and fragrances that can be utilized include ACALEA TBHQ,ACET C-6, ALLYL AMYL GLYCOLATE, ALPHA TERPINEOL, AMBRETTOLIDE, AMBRINOL95, ANDRANE, APHERMATE, APPLELIDE, BACDANOL®, BERGAMAL, BETA IONONEEPDXIDE, BETA NAPHTHYL ISO-BUTYL ETHER, BICYCLONONALACTONE, BORNAFIX®,CANTHOXAL, CASHMERAN®, CASHMERAN® VELVET, CASSIFFIX®, CEDRAFIX,CEDRAMBER®, CEDRYL ACETATE, CELESTOLIDE, CINNAMALVA, CITRAL DIMETHYLACETATE, CITROLATET™, CITRONELLOL 700, CITRONELLOL 950, CITRONELLOLCOEUR, CITRONELLYL ACETATE, CITRONELLYL ACETATE PURE, CITRONELLYLFORMATE, CLARYCET, CLONAL, CONIFERAN, CONIFERAN PURE, CORTEX ALDEHYDE50% PEOMOSA, CYCLABUTE, CYCLACET®, CYCLAPROP®, CYCLEMAX™, CYCLOHEXYLETHYL ACETATE, DAMASCOL, DELTA DAMASCONE, DIHYDRO CYCLACET, DIHYDROMYRCENOL, DIHYDRO TERPINEOL, DIHYDRO TERPINYL ACETATE, DIMETHYLCYCLORMOL, DIMETHYL OCTANOL PQ, DIMYRCETOL, DIOLA, DIPENTENE, DULCINYL®RECRYSTALLIZED, ETHYL-3-PHENYL GLYCIDATE, FLEURAMONE, FLEURANIL, FLORALSUPER, FLORALOZONE, FLORIFFOL, FRAISTONE, FRUCTONE, GALAXOLIDE® 50,GALAXOLIDE® 50 BB, GALAXOLIDE® 50 IPM, GALAXOLIDE® UNDILUTED,GALBASCONE, GERALDEHYDE, GERANIOL 5020, GERANIOL 600 TYPE, GERANIOL 950,GERANIOL 980 (PURE), GERANIOL CFT COEUR, GERANIOL COEUR, GERANYL ACETATECOEUR, GERANYL ACETATE, PURE, GERANYL FORMATE, GRISALVA, GUAIYL ACETATE,HELIONAL™, HERBAC, HERBALIMET™, HEXADECANOLIDE, HEXALON, HEXENYLSALICYLATE CIS 3-, HYACINTH BODY, HYACINTH BODY NO. 3, HYDRATROPICALDEHYDE.DMA, HYDROXYOL, INDOLAROME, INTRELEVEN ALDEHYDE, INTRELEVENALDEHYDE SPECIAL, IONONE ALPHA, IONONE BETA, ISO CYCLO CITRAL, ISO CYCLOGERANIOL, ISO E SUPER®, ISOBUTYL QUINOLINE, JASMAL, JESSEMAL®,KHARISMAL®, KHARISMAL® SUPER, KHUSINIL, KOAVONE®, KOHINOOL®,LIFFAROMET™, LIMOXAL, LINDENOL™, LYRAL®, LYRAME SUPER, MANDARIN ALD 10%TRIETH, CITR, MARITIMA, MCK CHINESE, MEIJIFF™, MELAFLEUR, MELOZONE,METHYL ANTHRANILATE, METHYL IONONE ALPHA EXTRA, METHYL IONONE GAMMA A,METHYL IONONE GAMMA COEUR, METHYL IONONE GAMMA PURE, METHYL LAVENDERKETONE, MONTAVERDI®, MUGUESIA, MUGUET ALDEHYDE 50, MUSK Z4, MYRACALDEHYDE, MYRCENYL ACETATE, NECTARATET™, NEROL 900, NERYL ACETATE,OCIMENE, OCTACETAL, ORANGE FLOWER ETHER, ORIVONE, ORRINIFF 25%,OXASPIRANE, OZOFLEUR, PAMPLEFLEUR®, PEOMOSA, PHENOXANOL®, PICONIA,PRECYCLEMONE B, PRENYL ACETATE, PRISMANTOL, RESEDA BODY, ROSALVA,ROSAMUSK, SANJINOL, SANTALIFFT™, SYVERTAL, TERPINEOL, TERPINOLENE 20,TERPINOLENE 90 PQ, TERPINOLENE RECT., TERPINYL ACETATE, TERPINYL ACETATEJAX, TETRAHYDRO, MUGUOL®, TETRAHYDRO MYRCENOL, TETRAMERAN, TIMBERSILKT™,TOBACAROL, TRIMOFIX® O TT, TRIPLAL®, TRISAMBER®, VANORIS, VERDOX™,VERDOX™ HC, VERTENEX®, VERTENEX® HC, VERTOFIX® COEUR, VERTOLIFF,VERTOLIFF ISO, VIOLIFF, VIVALDIE, ZENOLIDE, ABS INDIA 75 PCT MIGLYOL,ABS MOROCCO 50 PCT DPG, ABS MOROCCO 50 PCT TEC, ABSOLUTE FRENCH,ABSOLUTE INDIA, ABSOLUTE MD 50 PCT BB, ABSOLUTE MOROCCO, CONCENTRATE PG,TINCTURE 20 PCT, AMBERGRIS, AMBRETTE ABSOLUTE, AMBRETTE SEED OIL,ARMOISE OIL 70 PCT THUYONE, BASIL ABSOLUTE GRAND VERT, BASIL GRAND VERTABS MD, BASIL OIL GRAND VERT, BASIL OIL VERVEINA, BASIL OIL VIETNAM, BAYOIL TERPENELESS, BEESWAX ABS N G, BEESWAX ABSOLUTE, BENZOIN RESINOIDSIAM, BENZOIN RESINOID SIAM 50 PCT DPG, BENZOIN RESINOID SIAM 50 PCT PG,BENZOIN RESINOID SIAM 70.5 PCT TEC, BLACKCURRANT BUD ABS 65 PCT PG,BLACKCURRANT BUD ABS MD 37 PCT TEC, BLACKCURRANT BUD ABS MIGLYOL,BLACKCURRANT BUD ABSOLUTE BURGUNDY, BOIS DE ROSE OIL, BRAN ABSOLUTE,BRAN RESINOID, BROOM ABSOLUTE ITALY, CARDAMOM GUATEMALA CO2 EXTRACT,CARDAMOM OIL GUATEMALA, CARDAMOM OIL INDIA, CARROT HEART, CASSIEABSOLUTE EGYPT, CASSIE ABSOLUTE MD 50 PCT IPM, CASTOREUM ABS 90 PCT TEC,CASTOREUM ABS C 50 PCT MIGLYOL, CASTOREUM ABSOLUTE, CASTOREUM RESINOID,CASTOREUM RESINOID 50 PCT DPG, CEDROL CEDRENE, CEDRUS ATLANTICA OILREDIST, CHAMOMILE OIL ROMAN, CHAMOMILE OIL WILD, CHAMOMILE OIL WILD LOWLIMONENE, CINNAMON BARK OIL CEYLAN, CISTE ABSOLUTE, CISTE ABSOLUTECOLORLESS, CITRONELLA OIL ASIA IRON FREE, CIVET ABS 75 PCT PG, CIVETABSOLUTE, CIVET TINCTURE 10 PCT, CLARY SAGE ABS FRENCH DECOL, CLARY SAGEABSOLUTE FRENCH, CLARY SAGE C'LESS 50 PCT PG, CLARY SAGE OIL FRENCH,COPAIBA BALSAM, COPAIBA BALSAM OIL, CORIANDER SEED OIL, CYPRESS OIL,CYPRESS OIL ORGANIC, DAVANA OIL, GALBANOL, GALBANUM ABSOLUTE COLORLESS,GALBANUM OIL, GALBANUM RESINOID, GALBANUM RESINOID 50 PCT DPG, GALBANUMRESINOID HERCOLYN BHT, GALBANUM RESINOID TEC BHT, GENTIANE ABSOLUTE MD20 PCT BB, GENTIANE CONCRETE, GERANIUM ABS EGYPT MD, GERANIUM ABSOLUTEEGYPT, GERANIUM OIL CHINA, GERANIUM OIL EGYPT, GINGER OIL 624, GINGEROIL RECTIFIED SOLUBLE, GUAIACWOOD HEART, HAY ABS MD 50 PCT BB, HAYABSOLUTE, HAY ABSOLUTE MD 50 PCT TEC, HEALINGWOOD, HYSSOP OIL ORGANIC,IMMORTELLE ABS YUGO MD 50 PCT TEC, IMMORTELLE ABSOLUTE SPAIN, IMMORTELLEABSOLUTE YUGO, JASMIN ABS INDIA MD, JASMIN ABSOLUTE EGYPT, JASMINABSOLUTE INDIA, ASMIN ABSOLUTE MOROCCO, JASMIN ABSOLUTE SAMBAC,JONQUILLE ABS MD 20 PCT BB, JONQUILLE ABSOLUTE France, JUNIPER BERRY OILFLG, JUNIPER BERRY OIL RECTIFIED SOLUBLE, LABDANUM RESINOID 50 PCT TEC,LABDANUM RESINOID BB, LABDANUM RESINOID MD, LABDANUM RESINOID MD 50 PCTBB, LAVANDIN ABSOLUTE H, LAVANDIN ABSOLUTE MD, LAVANDIN OIL ABRIALORGANIC, LAVANDIN OIL GROSSO ORGANIC, LAVANDIN OIL SUPER, LAVENDERABSOLUTE H, LAVENDER ABSOLUTE MD, LAVENDER OIL COUMARIN FREE, LAVENDEROIL COUMARIN FREE ORGANIC, LAVENDER OIL MAILLETTE ORGANIC, LAVENDER OILMT, MACE ABSOLUTE BB, MAGNOLIA FLOWER OIL LOW METHYL EUGENOL, MAGNOLIAFLOWER OIL, MAGNOLIA FLOWER OIL MD, MAGNOLIA LEAF OIL, MANDARIN OIL MD,MANDARIN OIL MD BHT, MATE ABSOLUTE BB, MOSS TREE ABSOLUTE MD TEX IFRA43, MOSS-OAK ABS MD TEC IFRA 43, MOSS-OAK ABSOLUTE IFRA 43, MOSS-TREEABSOLUTE MD IPM IFRA 43, MYRRH RESINOID BB, MYRRH RESINOID MD, MYRRHRESINOID TEC, MYRTLE OIL IRON FREE, MYRTLE OIL TUNISIA RECTIFIED,NARCISSE ABS MD 20 PCT BB, NARCISSE ABSOLUTE FRENCH, NEROLI OIL TUNISIA,NUTMEG OIL TERPENELESS, OEILLET ABSOLUTE, OLIBANUM RESINOID, OLIBANUMRESINOID BB, OLIBANUM RESINOID DPG, OLIBANUM RESINOID EXTRA 50 PCT DPG,OLIBANUM RESINOID MD, OLIBANUM RESINOID MD 50 PCT DPG, OLIBANUM RESINOIDTEC, OPOPONAX RESINOID TEC, ORANGE BIGARADE OIL MD BHT, ORANGE BIGARADEOIL MD SCFC, ORANGE FLOWER ABSOLUTE TUNISIA, ORANGE FLOWER WATERABSOLUTE TUNISIA, ORANGE LEAF ABSOLUTE, ORANGE LEAF WATER ABSOLUTETUNISIA, ORRIS ABSOLUTE ITALY, ORRIS CONCRETE 15 PCT IRONE, ORRISCONCRETE 8 PCT IRONE, ORRIS NATURAL 15 PCT IRONE 4095C, ORRIS NATURAL 8PCT IRONE 2942C, ORRIS RESINOID, OSMANTHUS ABSOLUTE, OSMANTHUS ABSOLUTEMD 50 PCT BB, PATCHOULI HEART N° 3, PATCHOULI OIL INDONESIA, PATCHOULIOIL INDONESIA IRON FREE, PATCHOULI OIL INDONESIA MD, PATCHOULI OILREDIST, PENNYROYAL HEART, PEPPERMINT ABSOLUTE MD, PETITGRAIN BIGARADEOIL TUNISIA, PETITGRAIN CITRONNIER OIL, PETITGRAIN OIL PARAGUAYTERPENELESS, PETITGRAIN OIL TERPENELESS STAB, PIMENTO BERRY OIL, PIMENTOLEAF OIL, RHODINOL EX GERANIUM CHINA, ROSE ABS BULGARIAN LOW METHYLEUGENOL, ROSE ABS MOROCCO LOW METHYL EUGENOL, ROSE ABS TURKISH LOWMETHYL EUGENOL, ROSE ABSOLUTE, ROSE ABSOLUTE BULGARIAN, ROSE ABSOLUTEDAMASCENA, ROSE ABSOLUTE MD, ROSE ABSOLUTE MOROCCO, ROSE ABSOLUTETURKISH, ROSE OIL BULGARIAN, ROSE OIL DAMASCENA LOW METHYL EUGENOL, ROSEOIL TURKISH, ROSEMARY OIL CAMPHOR ORGANIC, ROSEMARY OIL TUNISIA,SANDALWOOD OIL INDIA, SANDALWOOD OIL INDIA RECTIFIED, SANTALOL, SCHINUSMOLLE OIL, ST JOHN BREAD TINCTURE 10 PCT, STYRAX RESINOID, STYRAXRESINOID, TAGETE OIL, TEA TREE HEART, TONKA BEAN ABS 50 PCT SOLVENTS,TONKA BEAN ABSOLUTE, TUBEROSE ABSOLUTE INDIA, VETIVER HEART EXTRA,VETIVER OIL HAITI, VETIVER OIL HAITI MD, VETIVER OIL JAVA, VETIVER OILJAVA MD, VIOLET LEAF ABSOLUTE EGYPT, VIOLET LEAF ABSOLUTE EGYPT DECOL,VIOLET LEAF ABSOLUTE FRENCH, VIOLET LEAF ABSOLUTE MD 50 PCT BB, WORMWOODOIL TERPENELESS, YLANG EXTRA OIL, YLANG III OIL and combinations ofthese.

The colorants can be among those listed in the Color Index Internationalby the Society of Dyers and Colourists. Colorants include dyes andpigments and include those commonly used for coloring textiles, paints,inks and inkjet inks. Some colorants that can be utilized includecarotenoids, arylide yellows, diarylide yellows, β-naphthols, naphthols,benzimidazolones, disazo condensation pigments, pyrazolones, nickel azoyellow, phthalocyanines, quinacridones, perylenes and perinones,isoindolinone and isoindoline pigments, triarylcarbonium pigments,diketopyrrolo-pyrrole pigments, thioindigoids. Cartenoids include, forexample, alpha-carotene, beta-carotene, gamma-carotene, lycopene, luteinand astaxanthin, Annatto extract, Dehydrated beets (beet powder),Canthaxanthin, Caramel, β-Apo-8′-carotenal, Cochineal extract, Carmine,Sodium copper chlorophyllin, toasted partially defatted cookedcottonseed flour, Ferrous gluconate, Ferrous lactate, Grape colorextract, Grape skin extract (enocianina), Carrot oil, Paprika, Paprikaoleoresin, Mica-based pearlescent pigments, Riboflavin, Saffron,Titanium dioxide, Tomato lycopene extract; tomato lycopene concentrate,Turmeric, Turmeric oleoresin, FD&C Blue No. 1, FD&C Blue No. 2, FD&CGreen No. 3, Orange B, Citrus Red No. 2, FD&C Red No. 3, FD&C Red No.40, FD&C Yellow No. 5, FD&C Yellow No. 6, Alumina (dried aluminumhydroxide), Calcium carbonate, Potassium sodium copper chlorophyllin(chlorophyllin-copper complex), Dihydroxyacetone, Bismuth oxychloride,Ferric ammonium ferrocyanide, Ferric ferrocyanide, Chromium hydroxidegreen, Chromium oxide greens, Guanine, Pyrophyllite, Talc, Aluminumpowder, Bronze powder, Copper powder, Zinc oxide, D&C Blue No. 4, D&CGreen No. 5, D&C Green No. 6, D&C Green No. 8, D&C Orange No. 4, D&COrange No. 5, D&C Orange No. 10, D&C Orange No. 11, FD&C Red No. 4, D&CRed No. 6, D&C Red No. 7, D&C Red No. 17, D&C Red No. 21, D&C Red No.22, D&C Red No. 27, D&C Red No. 28, D&C Red No. 30, D&C Red No. 31, D&CRed No. 33, D&C Red No. 34, D&C Red No. 36, D&C Red No. 39, D&C VioletNo. 2, D&C Yellow No. 7, Ext. D&C Yellow No. 7, D&C Yellow No. 8, D&CYellow No. 10, D&C Yellow No. 11, D&C Black No. 2, D&C Black No. 3 (3),D&C Brown No. 1, Ext. D&C, Chromium-cobalt-aluminum oxide, Ferricammonium citrate, Pyrogallol, Logwood extract,1,4-Bis[(2-hydroxy-ethyl)amino]-9,10-anthracenedionebis(2-propenoic)ester copolymers,1,4-Bis[(2-methylphenyl)amino]-9,10-anthracenedione,1,4-Bis[4-(2-methacryloxyethyl)phenylamino]anthraquinone copolymers,Carbazole violet, Chlorophyllin-copper complex, Chromium-cobalt-aluminumoxide, C.I. Vat Orange 1,2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol,16,23-Dihydrodinaphtho[2,3-a:2′,3′-i]naphth[2′,3′:6,7]indolo[2,3-c]carbazole-5,10,15,17,22,24-hexone,N,N′-(9,10-Dihydro-9,10-dioxo-1,5-anthracenediyl)bisbenzamide,7,16-Dichloro-6,15-dihydro-5,9,14,18-anthrazinetetrone,16,17-Dimethoxydinaphtho (1,2,3-cd:3′,2′,1′-lm) perylene-5,10-dione,Poly(hydroxyethyl methacrylate)-dye copolymers(3), Reactive Black 5,Reactive Blue 21, Reactive Orange 78, Reactive Yellow 15, Reactive BlueNo. 19, Reactive Blue No. 4, C.I. Reactive Red 11, C.I. Reactive Yellow86, C.I. Reactive Blue 163, C.I. Reactive Red 180,4-[(2,4-dimethylphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one(solvent Yellow 18), 6-Ethoxy-2-(6-ethoxy-3-oxobenzo[b]thien-2(3H)—ylidene)benzo[b]thiophen-3(2H)-one, Phthalocyanine green, Vinylalcohol/methyl methacrylate-dye reaction products, C.I. Reactive Red180, C.I. Reactive Black 5, C.I. Reactive Orange 78, C.I. ReactiveYellow 15, C.I. Reactive Blue 21, Disodium1-amino-4-[[4-[(2-bromo-1-oxoallyl)amino]-2-sulphonatophenyl]amino]-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate(Reactive Blue 69), D&C Blue No. 9, [Phthalocyaninato(2-)] copper andmixtures of these.

Other than in the examples herein, or unless otherwise expresslyspecified, all of the numerical ranges, amounts, values and percentages,such as those for amounts of materials, elemental contents, times andtemperatures of reaction, ratios of amounts, and others, in thefollowing portion of the specification and attached claims may be readas if prefaced by the word “about” even though the term “about” may notexpressly appear with the value, amount, or range. Accordingly, unlessindicated to the contrary, the numerical parameters set forth in thefollowing specification and attached claims are approximations that mayvary depending upon the desired properties sought to be obtained by thepresent invention. At the very least, and not as an attempt to limit theapplication of the doctrine of equivalents to the scope of the claims,each numerical parameter should at least be construed in light of thenumber of reported significant digits and by applying ordinary roundingtechniques.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains errornecessarily resulting from the standard deviation found in itsunderlying respective testing measurements. Furthermore, when numericalranges are set forth herein, these ranges are inclusive of the recitedrange end points (e.g., end points may be used). When percentages byweight are used herein, the numerical values reported are relative tothe total weight.

Also, it should be understood that any numerical range recited herein isintended to include all sub-ranges subsumed therein. For example, arange of “1 to 10” is intended to include all sub-ranges between (andincluding) the recited minimum value of 1 and the recited maximum valueof 10, that is, having a minimum value equal to or greater than 1 and amaximum value of equal to or less than 10. The terms “one,” “a,” or “an”as used herein are intended to include “at least one” or “one or more,”unless otherwise indicated.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the scope of the inventionencompassed by the appended claims.

What is claimed is:
 1. A method of processing materials, such as abiomass material, the method comprising; conveying a biomass materialthrough a first enclosure and exposing the biomass material to a firstdose of ionizing radiation to produce a first treated biomass material;and conveying the first treated biomass material through a secondenclosure and exposing the first treated biomass material to a seconddose of ionizing radiation to produce a second treated biomass material.2. The method of claim 1, wherein the first enclosure shares one or morecommon walls with the second enclosure.
 3. The method of claim 1,wherein the first and second dose of the ionizing radiation are appliedusing accelerated electrons from one or more electron accelerators. 4.The method of claim 3, wherein the electrons are accelerated to anenergy of between about 0.3 MeV and about 5 MeV.
 5. The method of claim1, wherein the first dose is between about 0.5 Mrad and about 20 Mrad.6. The method of claim 1, wherein the sum of the first and second doseis between about 10 Mrad and about 40 Mrad.
 7. The method of claim 1,wherein walls of both the first and second enclosures are fabricatedfrom discrete interconnecting blocks to provide photon-tight structures.8. The method of claim 1, further comprising conveying the biomassmaterial into the first enclosure and then conveying the first treatedbiomass out of the first enclosure and into the second enclosure.
 9. Themethod of claim 1, further comprising conveying the second treatedbiomass material out of the second enclosure.
 10. The method of claim 9,further comprising conveying the biomass into a third enclosure,conveying the biomass within the third enclosure and exposing the secondtreated biomass material to a third dose of ionizing radiation toproduce a third treated biomass material.
 11. The method of claim 10,wherein the conveying utilizes a pneumatic conveyor system and/or ascrew conveyer system.
 12. The method of claim 8, wherein the conveyinginto and/or out of enclosures occurs continuously.
 13. The method ofclaim 1, wherein the biomass material and/or the first treated biomassmaterial is/are conveyed by a vibratory conveyor within theenclosure(s).
 14. The method of claim 13, wherein conveying with thevibratory conveyor occurs continuously.
 15. The method of claim 1,wherein the first and second dose of ionizing radiation are appliedusing accelerated electrons produced by an accelerator, each acceleratoroperating at a power of between about 100 kW and about 400 kW.
 16. Abiomass treatment facility, comprising: a first conveying systemconfigured to convey a biomass material through a first enclosure whileexposing the biomass material to a first dose of ionizing radiation froma first electron accelerator to produce a first treated biomassmaterial; and a second conveying system configured to convey the firsttreated biomass material through a second enclosure while exposing thefirst treated biomass material to a second dose of ionizing radiationfrom a second electron accelerator to produce a second treated biomassmaterial.
 17. The facility of claim 16, wherein the first and secondenclosure share a common wall.
 18. The facility of claim 16, whereineach accelerator operates at a power of between about 100 kW and about300 kW.
 19. The facility of claim 16, wherein walls of both the firstand second enclosures are fabricated from discrete interconnectingblocks configured to provide a photo-tight structure.